S.A.T Math
posted by Mack on .
At Central Park Zoo,the ratio of sea lions to penguins is 4 to 11. If there are 84 more penguins than sea lions, how many sea lions are there?
The answer book says: C is the answer. The correct answer should yield a ratio of sea lions to Penguins of 4 to 11, so try out choice C. If there are 48 sea lions, there are 48+84=132 penguins, so the ratio of sea lions to penguins is 48/132=4/11, which is just what we want.
How did they know to pick choice C??

wait:
132 penguins 4
 = 
48 sea lions 11
i don't think the 2 fractions = eachother(11 doesn't go into 48 
wait no im wrong ignore thelast post

c IS right because 48/132=4/11:
48 divided by 4=12
132 divided by 11=12 
right. Here is they knew to pick those numbers.
Let number sea lions = S
let number penquins = P
We know two things.
S/P = 4/11 AND
S+84=P
Two equations with two unknowns. Solve simultaneously for S and P.
S is 48 and P is 132
and 48/132 is in the ratio of 4/11 
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