All GMAT Math Resources
Example Questions
Example Question #3 : Decimals
and are fractions in lowest terms.
True or false: The result can be represented by an integer or a terminating decimal.
Statement 1: Both denominators are even.
Statement 2: Both denominators are multiples of 3.
BOTH statements TOGETHER are insufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Assume both statements to be true. A multiple of both 2 and 3 is also a multiple of 6, so both denominators are multiples of 6. Examine these two examples:
In both examples, the conditions of the problem, including both statements, are met, but in only one is the sum equivalent to a terminating decimal or integer.
Example Question #241 : Arithmetic
and are fractions in lowest terms.
True or false: The result can be represented by an integer or a terminating decimal.
Statement 1: Neither denominator is a multiple of 5.
Statement 2: Both denominators are powers of 2.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Assume Statement 1 alone. Examine these two examples:
Both fit the main condition and that of Statement 1, but in only one case is the sum equal to a terminating decimal or integer.
Assume Statement 2 alone. A necessary and sufficient condition for a lowest-terms fraction to be equivalent to a terminating decimal is that its only prime factors are 2 and 5. By Statement 2, both denominators have 2 as their only prime factor, so both can be represented by terminating decimals; their product must be terminating as well.
Example Question #242 : Arithmetic
and are fractions in lowest terms.
True or false: The result can be represented by an integer or a terminating decimal.
Statement 1: The denominator of is a power of 7.
Statement 2: The denominator of is a power of 3.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Assume both statements. Examine these two examples; both fit the main condition and those given in both statements.
In only one case is the product equivalent to an integer or a terminating decimal.
Example Question #243 : Arithmetic
and are fractions in lowest terms.
True or false: The result can be represented by an integer or a terminating decimal.
Statement 1: The denominator of is three times the numerator of .
Statement 2: The denominator of is six times the numerator of .
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Assume Statement 1 alone. Rewrite the fractions as follows:
, where - that is, their lowest-terms representations.
By Statement 1, , so . Therefore,
Since is in lowest terms, is not a multiple of 3, so the 3 must remain in the denominator, even if the and the can be reduced. Since a fraction which, in lowest terms, has a denominator with any prime factor other than 2 or 5 cannot be represented by an integer or a terminating decimal, Statement 1 proves that has a repeating decimal as its equivalent.
A similar argument can be used to demonstrate that Statement 2 proves the same of .
Example Question #244 : Arithmetic
and are fractions in lowest terms.
True or false: The result can be represented by an integer or a terminating decimal.
Statement 1: The denominator of is five times the numerator of .
Statement 2: The denominator of is eight times the numerator of .
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Assume Statement 1 alone. Examine these examples:
In both cases, the main conditon and that of Statement 1 are satisfied, but in only one case can the result be represented by a terminating decimal or integer.
A similar argument shows Statement 2 alone to be insufficient:
Assume both statements. Then rewrite the fractions as follows:
, where - that is, their lowest-terms representations.
By Statement 1, ; by Statement 2, . Therefore,
,
and their product is
,
a terminating decimal.
Example Question #245 : Arithmetic
Solve for in the following equation.
I) is equivalent to seventy nine hundredths.
II) The slope of the line parallel to this equation is .
Statement II is sufficient to answer the question, but statement I is not sufficient to answer the question.
Neither statement is sufficient to answer the question. More information is needed.
Either statement is sufficient to answer the question.
Statement I is sufficient to answer the question, but statement II is not sufficient to answer the question.
Both statements are needed to answer the question.
Statement I is sufficient to answer the question, but statement II is not sufficient to answer the question.
We have one equation and two unknowns. To find x, we need to find y.
I) Tells us that y is .79 therefore we can plug this value into our equation and solve for x.
Plugging in the y value from Statement I and using algebraic operations to solve for x.
Multiply first term.
Subtract 4.74 from both sides.
Divide by -13.
II) Is irrelevant.
Therefore Statement I) alone is sufficient to answer the question but Statement II) alone is not.
Example Question #1 : Dsq: Understanding Real Numbers
Is z a negative number?
(1)
(2) is positive
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
EACH statement ALONE is sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(1) Subtracting from both sides of shows that , so must be negative SUFFICIENT
(2) Subtracting 4 from both sides of gives . Therefore, for this statement, can be negative but is not necessarily negative. NOT SUFFICIENT.
Example Question #2 : Dsq: Understanding Real Numbers
If , , and are points on the number line, what is the distance between and ?
(1) The distance between and is 7.
(2) The distance between and is 12.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
D. EACH statement ALONE is sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
Looking at statements (1) and (2) separately, there is no information about the distance between and . Looking at statements (1) and (2) together, there are two possibilities: 1) and are on different sides of , and the distance between them is 19; 2) and are on the same side of , and the distance between them is 5. Therefore, we cannot get the only possible answer to this question based on the two statements.
Example Question #1 : Real Numbers
Data sufficiency question- do not actually solve the question
How many children are attending a party?
1. If 6 more children attend the party, there will be 24 children there.
2. If 10 children leave the party, there will be less than 12 children in attendance.
Both statements taken together are sufficient to ansewr the question, but neither statement alone is sufficient
Statement 1 alone is sufficient, but statement 2 alone is not sufficient to answer the question
Each statement alone is sufficient
Statements 1 and 2 together are not sufficient, and additional information is needed to answer the question
Statement 2 alone is sufficient, but statement 1 alone is not sufficient to answer the question
Statement 1 alone is sufficient, but statement 2 alone is not sufficient to answer the question
Statement 1 precisely tells how many children are attending the party while Statement 2 only provides a range.
Example Question #2 : Dsq: Understanding Real Numbers
A sandwich shop offers a discount in which customers pay $2.99 for each additional sandwich after purchasing their first sandwich. Emily bought her first sandwich for $4.95. If she purchased 5 additional sandwiches to take home, then the total amount she paid is equivalent to which of the following?
The price of 6 sandwiches can be expressed as . Regrouping is needed since this is not in the answer choices. If $3.00 is used instead of $2.99, each of the five additional sandwiches is .01 too high and the total is .05 too high. Therefore, this amount needs to be subtracted from the $4.95.