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2 votes
Candice spent 5 1/4 hours doing her homework. Her brother, Ronald, spent 1/2 that number of hours doing his homework. How many hours did Ronald spend on his homework?

A.10/8
B.2 5/8
C.5 1/8
D.21/2

User Faruq
by
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2 Answers

1 vote
5 1/4 times 1/2 = 2.625. as a fraction 2.625 is 2 5/8 because .625 could be drawn out to 625/1000 125 goes into 625 and 1,000 625 divided by 125 = 5 and 1,000 divided by 125 is 8 we already had 2 so 2 5/8

Hope I helped =)

User Shyann
by
7.0k points
5 votes

Let

x-----> the number of hours that Candice spent doing her homework

y-----> the number of hours that Ronald spent doing his homework

we know that


x=5(1)/(4)\ hours

convert mixed number to an improper fraction


5(1)/(4)\ hours=(5*4+1)/(4)= (21)/(4)\ hours

so


x=(21)/(4)\ hours -------> equation A


y=(1)/(2)x ------> equation B

Substitute equation A in equation B


y=(1)/(2)*(21)/(4)=(21)/(8)\ hours

convert an improper fraction to a mixed number


(21)/(8)\ hours=2.625=2+0.625=2+(5)/(8)=2(5)/(8)\ hours

therefore

the answer is the option B


2(5)/(8)\ hours

User Brian Rogers
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7.4k points