# Math

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I have \$100.00 dollars to spend to buy 100 animals. Cows cost \$50.00 each, sheep cost \$3.00 each, pigs cost \$2.00 each and chicks cost \$0.10 each. How many of each do I need to buy to spend \$100.00 dollars and have 100 aninals?

• Math - ,

We use the assumption method that we need at least 1 of each animal..

Cow @ \$50
Sheep @ \$3
Pig @ \$2
Chicks @ 10cents

We can easily observe that only 1 cow can be purchased to enable purchase of other animals.

Now we are left with 99 more animals to buy in \$50

Easily observable that we need to buy Chicks in multiples of 10
So
10 20 30 40 50 60 70 80 90

Let us draw a chart now

10 chicks \$1 \$49 (1sheep-15 sheep)(2pigs-23pigs) even if we count max animals in this assumption
(10chicks + 1sheep + 23pigs =34 but we need 99..)
So we have to increase the number of chicks..atleast by 6-7 times more

Lets assume 80 chicks..

80 chicks will cost us \$8
We will remain with (\$100-\$50-\$8=42)
Total animals 80chicks+1cow = 81
Remaining amount \$42 and animals 19

Lets try some combinations
42-6(\$3*2) =36
36/\$2= 18
Hence 2 sheep and 18 pigs is wrong since it equals 20 and we need only 19..
Guess we are pretty close

Lets try
42-12(\$3*4)= \$30
30/\$2= 15

BANG ON.. 4 SHEEP AND 15 PIGS = 19

1 COW \$50
4 SHEEP \$12
15 PIGS \$30
80 CHICKS \$8