SOLUTION: three girls share a packet of sweet. the first received 2/5 of the sweets. the second received 5/9 of the remainder and the third got 8 sweets.how many sweet were in the packet?

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: three girls share a packet of sweet. the first received 2/5 of the sweets. the second received 5/9 of the remainder and the third got 8 sweets.how many sweet were in the packet?      Log On


   



Question 1129133: three girls share a packet of sweet. the first received 2/5 of the sweets. the second received 5/9 of the remainder and the third got 8 sweets.how many sweet were in the packet?
Found 2 solutions by ankor@dixie-net.com, MathTherapy:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
three girls share a packet of sweet. the first received 2/5 of the sweets.
the second received 5/9 of the remainder and the third got 8 sweets.
how many sweet were in the packet?
:
let a = total amt of sweets
change 2/5 to .4, simplify dealing with fractions
a = .4a + 5%2F9(a-.4a) + 8
a = .4a + 5%2F9(.6a) + 8
multiply equation by 9 to get rid of the denominator
9a = 9(.4a) + 5(.6a) + 9(8)
9a = 3.6a + 3a + 72
9a = 6.6a + 72
9a - 6.6a = 72
2.4a = 72
a = 72/2.4
a = 30 sweets in the packet
:
:
See if that checks out
2%2F5 * 30 = 12 for the 1st girl
5%2F9 * 18 = 10 for the 2nd girl (subtracted 12 from the total)
3rd girl: 8
----------------
total 30

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

three girls share a packet of sweet. the first received 2/5 of the sweets. the second received 5/9 of the remainder and the third got 8 sweets.how many sweet were in the packet?
With the 1st girl getting 2%2F5, 3%2F5 remains
With the 2nd girl getting 5%2F9 of remainder, matrix%281%2C6%2C+%284%2F9%29%2C+%22%2A%22%2C+%283%2F5%29%2C+or%2C+4%2F15%2C+remains%29
With the 3rd receiving matrix%281%2C3%2C+4%2F15%2C+or%2C+8%29, we get: matrix%281%2C3%2C+4%2F15%2C+%22=%22%2C+8%2FN%29, with N being the original number
4N = 8(15) ------ Cross-multiplying
N, or original number = highlight_green%28matrix%281%2C4%2C+8%2815%29%2F4%2C+%22=%22%2C+30%2C+sweets%29%29