6th grade math
posted by m-cook .
on a farm there is 18 pigs and chickens (all together). There are 52 legs, how many pigs and how many chickens are there? Show how you got your answer. i know there are 10 chickens and 8 pigs, but i did that through trial and error, can you help me figure out the right math to do for this problem.
There are two ways to do it, the farmer's way and the mathematicians's. I prefer the farmer's way.
First, the farmer's way:
We have 18 animals and 52 legs.
If we have 9 of each, that makes an average of 3 legs each animal, we get 3*18=54 legs. We only have 52. So change one pig (9-1=8) for a chicken (9+1=10) to get 52 legs (two less). That makes 10 chickens and 8 pigs. No calculators, no pain either.
Now the mathematicians way:
Let p be the number of pigs, then the number of chickens is (18-p).
The total number of legs is thus
4*p + 2(18-p) = 52
2p = 52-36
p = 16/2
(18-p) = 18-8 = 10
Answer: there are 8 pigs and 10 chickens.
make a funny sentense for each math word