SOLUTION: The cost for 2 adults and 5 children to eat is $45.50. 1 adult and 1 child is $15. How much os a childs meal?

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Question 1061900: The cost for 2 adults and 5 children to eat is $45.50. 1 adult and 1 child is $15. How much os a childs meal?
Found 2 solutions by jorel555, josmiceli:
Answer by jorel555(1290) About Me  (Show Source):
You can put this solution on YOUR website!
Let a be adult, and c be a child. Then:
a+c=15
2a+5c=45.5 So:
2a+2c=30
3c=15.5
c=$5.167 as the cost of a child's meal. ☺☺☺☺
a=$9.833

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = the cost of an adult's meal
Let +b+ = the cost of a child's meal
------------------------------------
(1) +2a+%2B+5b+=+4550+ ( in cents )
(2) +a+%2B+b+=+1500+ ( in cents )
------------------------------------
Multiply both sides of (2) by +2+
and subtract (2) from (1)
(1) +2a+%2B+5b+=+4550+
(2) +-2a+-+2b+=+-+3000+
-------------------------
+3b+=+1550+
+b+=+516.67+ cents
+b+=+5.17+ dollars
and
(2) +a+%2B+b+=+1500+
(2) +a+=+1500+-+516.67+
(2) +a+=+983.33+ cents
(2) +a+=+9.83+
----------------------------
A child's meal is $5.17
----------------------------
check:
(1) +2a+%2B+5b+=+45.5+ ( in dollars )
(1) +2%2A9.83+%2B+5%2A5.17+=+45.5+
(1) +19.66+%2B+25.85+=+45.52+
error due to rounding off, I think
Check my math and maybe get another opinion, too