All ISEE Upper Level Quantitative Resources
Example Questions
Example Question #91 : How To Find The Solution To An Equation
A hat costs $70.80 after a 20% discount. How much did the hat cost before the discount?
It is impossible to tell from the information given.
Since $70.80 is the price after a 20% discount off the original price, it is 80% of that original price. The problem is equivalent to asking:
$70.80 is 80% of what amount?
Let be the price before discount.
Example Question #91 : How To Find The Solution To An Equation
Which is the greater quantity?
(A)
(B)
(B) is greater
(A) is greater
It is impossible to determine which is greater from the information given
(A) and (B) are equal
(B) is greater
, so .
Substitute for in the other equation:
, so (B) is greater.
Example Question #93 : How To Find The Solution To An Equation
A line includes the points and . Which is the greater quantity?
(A) The -coordinate of the -intercept.
(B) The -coordinate of the -intercept.
It is impossible to determine which is greater from the information given
(A) and (B) are equal
(A) is greater
(B) is greater
(A) is greater
We can figure out the equation of the line as follows:
Set . Substitute in the slope formula.
The slope is
In the slope-intercept formula, we set
and solve for :
The equation is
The -intercept is . To find the -intercept, we substitute 0 for :
The -intercept is .
This makes (A), the -coordinate of the -intercept, greater.
Example Question #91 : How To Find The Solution To An Equation
Define and .
What is the domain of the function ?
has as its domain the set of values of for which its radicand is nonnegative; that is,
or
Similarly, has as its domain the set of values of for which its radicand is nonnegative; that is,
or
The domain of the sum of two functions is the intersection of the domains of the two individual functions. This intersection is
Example Question #93 : How To Find The Solution To An Equation
Define and .
Which is the greater quantity?
(A)
(B)
It is impossible to determine which is greater from the information given
(A) is greater
(B) is greater
(A) and (B) are equal
(A) and (B) are equal
Substitute and to determine the values of the respective expressions:
The expressions are equal.
Example Question #91 : How To Find The Solution To An Equation
For all real numbers and , define an operation as follows:
For which value of is the expression undefined?
so
This expression is undefined if and only if the denominator is equal to 0, so
Example Question #92 : How To Find The Solution To An Equation
A line includes the points and . What is the -intercept of this line (-coordinate rounded to the nearest tenth)?
Let
We calculate the slope as follows:
Apply the point-slope formula setting
:
Set to find the -coordinate of the -intercept:
The -intercept is (approximately at)
Example Question #95 : How To Find The Solution To An Equation
A line includes the points and . What is the -intercept of this line?
Let
We calculate the slope as follows:
Apply the point-slope formula setting
Set to find the -coordinate of the -intercept:
The -intercept is .
Example Question #92 : How To Find The Solution To An Equation
A line includes the points and . Which of these is the slope of that line?
The correct answer is not among the other choices
Let
We calculate the slope as follows:
Example Question #95 : How To Find The Solution To An Equation
For all real numbers and , define an operation as follows:
Let be a positive number. Then which is the greater quantity?
(A)
(A)
(A) is greater
(A) and (B) are equal
It is impossible to determine which is greater from the information given
(B) is greater
(B) is greater
Substitute each pair of expressions:
We can compare these fractions by writing them with a common denominator:
regardless of the value of , making (B) greater.