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Mary's 3 hamsters each eat three-eighths of cup of grain a day, if she has 6 and 3/4 cups of grain, how many days will the grain last?

User Ben Tidman
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2 Answers

3 votes
Hello!

3/8 times 3 equals 9/8 which is also 1 1/8. If you multiply 3/4 by two (numerator and denominator) then you will get 6/8. And if you multiply 9/8( I just find it easier with 9/8) by 6 you will get 54/8. And the grain will last for 6.75 days.

I may be wrong let me know.
Hope this helps!
User DaveEdelstein
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3 votes

Answer:

6 days

Explanation:

Each hamster eat
(3)/(8) of a cup of grain a day.

So in one day, the three hamsters eat:


3*((3)/(8) )=(3*3)/(8) =(9)/(8) cups

And since we know that Mary has 6
(3)/(4) cups of grain.

We need to convert this quantity into a fraction:


6(3)/(4)=(6*4+3)/(4)=(27)/(4)

she has
(27)/(4) cups of grain.

To find how many days the grain will last, we need to divide the total amount of grain she has (
(27)/(4) cups) by the amount that the three hamsters eat together in one day (
(9)/(8) cups):


(27)/(4) ÷
(9)/(8)

and we use the rule to divide fractions:


(x)/(y) ÷
(z)/(w) =(x*w)/(y*z)

this way we get:


(27)/(4) ÷
(9)/(8)
=(27*8)/(4*9)=(216)/(36)=6

the grain will last 6 days

User Tafa
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