All SAT Math Resources
Example Questions
Example Question #1 : How To Find The Lowest / Least Common Denominator
3/5 + 4/7 – 1/3 =
72/89
88/105
7/9
4/3
3/37
88/105
We need to find a common denominator to add and subtract these fractions. Let's do the addition first. The lowest common denominator of 5 and 7 is 5 * 7 = 35, so 3/5 + 4/7 = 21/35 + 20/35 = 41/35.
Now to the subtraction. The lowest common denominator of 35 and 3 is 35 * 3 = 105, so altogether, 3/5 + 4/7 – 1/3 = 41/35 – 1/3 = 123/105 – 35/105 = 88/105. This does not simplify and is therefore the correct answer.
Example Question #1 : Lowest Common Denominator
What is the lowest common denominator of the fractions below?
In order to find the lowest common denominator, you must first list the multiples of each of the denominators of the three fractions:
The lowest common denominator between these three sets of multiples is .
Example Question #631 : Arithmetic
What is the Lowest Common Denominator of ,and ?
The smallest number they all have in common in .
Example Question #151 : Arithmetic
Simplify x/2 – x/5
3x/10
5x/3
3x/7
7x/10
2x/7
3x/10
Simplifying this expression is similar to 1/2 – 1/5. The denominators are relatively prime (have no common factors) so the least common denominator (LCD) is 2 * 5 = 10. So the problem becomes 1/2 – 1/5 = 5/10 – 2/10 = 3/10.
Example Question #631 : Arithmetic
If is an integer, which of the following is a possible value of ?
, which is an integer (a number with no fraction or decimal part). All the other choices reduce to non-integers.
Example Question #632 : Arithmetic
Simplify:
First, let's simplify . The greatest common factor of 4 and 12 is 4. 4 divided by 4 is 1 and 12 divided by 4 is 3. Therefore .
To simply fractions with exponents, subtract the exponent in the numerator from the exponent in the denominator. That leaves us with or
Example Question #1 : How To Simplify A Fraction
Which of the following is not equal to 32/24?
160/96
224/168
16/12
96/72
4/3
160/96
24/32 = 1.33
16/12 =1.33
224/168 =1.33
4/3 = 1.33
96/72 = 1.33
160/96 = 1.67
Example Question #1 : How To Simplify A Fraction
Find the root of
Can not be determined
The root occurs where . So we substitute 0 for .
This means that the root is at .
Example Question #5 : Simplifying Fractions
Simplify the fraction below:
The correct approach to solve this problem is to first write factors for the numerator and the denominator:
The highest common factor is 5. Therefore, you can divide the numerator and denominator by 5 in order to get a simplified fraction.
Thus the numerator becomes,
and the denominator becomes .
Therefore the final answer is .
Example Question #2 : How To Simplify A Fraction
Simplify:
Find the common factors of the numerator and denominator. They both share factors of 2,4, and 8. For simplicity, factor out an 8 from both terms and simplify.