85.8k views
4 votes
9/4 - 7/10 i cant figure this out

2 Answers

6 votes

Answer:

9/4 - 7/10= 31/20=1 11/20

Explanation:

look first for their LCM=20

2 4 10

2 2 5

5 1 5

1 1

then you divide the LCM which is 20by one of the denominator and multiply by the numerator over denominator

20/4*9=45/20

20/10*7=14/20

now both have the same denominator so we just subtract the numerators

45-14/20=31/20

now we have subtracted and our answer is in improper fraction so we need to change to mixed fraction

31/20=1 11/20

User Henrik Pingel
by
4.3k points
3 votes

Answer:

The answer is 31/20.

Explanation:

First, you have to have both fractions the same denorminator :


(9)/(4) - (7)/(10)


(9 * 5)/(4 * 5) - (7 * 2)/(10 * 2)


(45)/(20) - (14)/(20)

Next, you have to subtract :


(45)/(20) - (14)/(20)


(45 - 14)/(20)


(31)/(20)

User Emil Lerch
by
3.7k points