Question 824314
I need more detail solution: 
A girl has orange, yellow and red sweets. 
number = o + y + r
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She has exactly twice as many red as yellow.
number = o + y + 2y = o+3y
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After eating fourteen orange sweets, she has two less orange than yellow sweets.
o-14 = y-2
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Also, the number of orange sweets now are 20% of the total number of sweets she had at the beginning.
o-14 = (1/5)(o+3y)
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How many sweets did she have at the beginning?
Using o-14 = (1/5)(o+3y) and o-14 = y-2 you get::
5o-70 = o+3y
4o - 3y = 70
o = y+12
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Solve for "y":
4y+48-3y = 70
y = 22 (# of yellow sweets)
o = y + 12 = 34 (# of orange sweets)
r = 2y = 44 (# of red sweets)
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total number:: 22 + 34 + 44 = 100
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Cheers,
Stan H.
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