SOLUTION: An animal shelter spends $1.50 per day to care for each bird and $7.00 per day to care for each cat. Hailey noticed that the shelter spent $74.50 caring for birds and cats on Frida

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: An animal shelter spends $1.50 per day to care for each bird and $7.00 per day to care for each cat. Hailey noticed that the shelter spent $74.50 caring for birds and cats on Frida      Log On


   



Question 1012773: An animal shelter spends $1.50 per day to care for each bird and $7.00 per day to care for each cat. Hailey noticed that the shelter spent $74.50 caring for birds and cats on Friday. Hailey found a record showing that there were a total of 24 birds and cats on Friday. How many birds were at the shelter on Friday?
Found 2 solutions by fractalier, josmiceli:
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Call the number of birds and cats, b and c. Then we can write
1.50b + 7c = 74.50 and
b + c = 24
Let's multiply the second one by 7 and subtract from the first one...
1.50b + 7c = 74.50
-(7b + 7c = 168)
---------------------
-5.5b = -93.50
and
b = 17 birds
c = 24 - 17 = 7 cats

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +b+ = number of birds at shelter on friday
Let +c+ = number of cats at shelter on friday
-------------------
(1) +b+%2B+c+=+24+
(2) +1.5b+%2B+7c+=+74.5+
---------------------
(2) +15b+%2B+70c+=+745+
(2) +3b+%2B+14c+=+149+
Multiply both sides of (1) by +3+
and subtract (1) from (2)
-------------------------
(2) +3b+%2B+14c+=+149+
(1) +-3b+-+3c+=+-72+
----------------------
+11c+=+77+
+c+=+7+
and
(1) +b+%2B+c+=+24+
(1) +b+%2B+7+=+24+
(1) +b+=+17+
There were 17 birds at the shelter on friday
check:
(2) +1.5b+%2B+7c+=+74.5+
(2) +1.5%2A17+%2B+7%2A7+=+74.5+
(2) +25.5+%2B+49+=+74.5+
(2) +74.5+=+74.5+
OK