The length of time, y hours, it takes to put a jigsaw puzzle together is inversely proportional to the number of children, x, working on it. It takes 16 children 6 hours to put the jigsaw puzzle together. How many children are needed to put the same jigsaw puzzle together in 4 hours?

24 children

Step-by-step explanation:

If the length of time, y hours, it takes to put a jigsaw puzzle together is inversely proportional to the number of children, x, this is represented as;

k is the constant of proportionality

If it takes 16 children 6 hours to put the jigsaw puzzle together, this means at x = 16, y = 6

Substitute:

6 = k/16

k = 6*16

k = 96

W are to find number of children needed to put the same jigsaw puzzle together in 4 hours, this is done by substituting k = 96 and y = 4 into the expression y = k/x

y = 96/4

y = 24

Hence it will take 24 children to put the same jigsaw puzzle together in 4 hours

ad = ae + ed = y + 7

similar triangles therefor

ac/ab = ad/ae

6/4 = (y + 7) / y

cross multiply

6y = 4(y + 7)

6y = 4y + 28

2y = 28

y = 14

step-by-step explanation: