Answer:
140
Step-by-step explanation:
We have been given two fractions
and
. We are asked to find the least common denominator of both fractions.
To find the least common denominator of both fractions, we will find least common multiple of 20 and 28.
Prime factorization of 20: 
Prime factorization of 28: 
Least common multiple of 20 and 28 would be:
.
Therefore, the least common denominator of both fractions would be 140.
The answer is D.
350 multiplied by 6 is equal to 2100
350 * 0.5 (30 minutes) is equal to 175
2100 + 175 = 2275
Answer:
48 in. x 64 in. is the correct answer
Remark
Many calculators have a key that will do this in one step. Mine is one of them. So let's start with the answer and then we'll do it the long way.
9C3 = 84. You put it into your calculator as 9 2nF nCr 3 =
Solution

3*4*7 = 84 which is what you set out to show.