Problema Solution
One half of the birds at a pet store are yellow. Tara buys one of the yellow birds. Then one third of the birds at the store are yellow. How many yellow birds were at the pet store before Tara bought one?
I believe the answer is 4. Not too sure
Answer provided by our tutors
Let 'x' represent the number of all the birds in the store.
x/2 = the number of yellow birds
x/2 - 1 = x/3
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click here to see the equation solved for x
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x = 6 birds
Half of 6 birds is 3 yellow birds.
Lets check:
We have 3 yellow birds, Tara buys 1, then there are 3-1 = 2 yellow birds left and that is 2/6 = 1/3 of the total number of birds. So the answer is: there were 3 yellow birds in the store.
If we assume the answer is 4 yellow birds this will mean that the total number of birds in the store is 2*4 = 8.
Tara buys 1 yellow bird so there are 4-1 = 3 yellows birds left and that is 3/8 and not 1/3 of the birds in the store. Therefor 4 is not the right answer.