Question

Mr. Alvarado needs 15 1/8 pounds of chicken feed to fill his feeder. He has one bag of chicken feed that weighs 3 1/2 pounds and another bag of chicken feed that weighs 2 3/4 pounds. How many more pounds of chicken feed does Mr. Alvarado need to fill the chicken feeder?
A: 9 1/8 Lbs

B: 8 7/8 Lbs

C: 9 7/8 Lbs

D: 6 1/4 Lbs

Answer 1

Answer:

B: 8 7/8 Lbs

Step-by-step explanation:

answer = $15\frac{1}{8} -3\frac{1}{2} -2\frac{3}{4}$

step 1 find a common denominator

common denominator - 8

* apply *

$\frac{1^*^1}{8^*^8} =\frac{1}{8} \\\\\frac{1^*^4}{2^*^4} =\frac{4}{8} \\\\\frac{3^*^2}{4^*^2} =\frac{6}{8}$

now we have

$15\frac{1}{8} -3\frac{4}{8} -2\frac{6}{8}$

step 2 make each fraction a improper fraction

We can do this my multiplying the big number by the denominator and adding that to the numerator.

$15*8=120\\120+1=121\\\frac{121}{8} \\\\3*8=24\\24+4=28\\\frac{28}{8} \\\\2*8=16\\16+6=22\\\frac{22}{8}$

now we have

$\frac{121}{8} -\frac{28}{8} -\frac{22}{8}$

Now we can subtract

remember when subtracting fractions you only subtract the numerators. ( so we keep the denominator as 8 )

so 121 - 28 - 22 = 71

so the answer is $\frac{71}{8}$

finally we want to change the answer back into a mixed fraction

To do this we divided 71 and 8

8 can go into 71 8 times

8 * 8 = 64

71 - 64 = 7

We're left with $8\frac{7}{8}$