Question 33183
Let number of cars washed be "c"
Money from that work is "3c"
Let number of trucks washed be "t"
Money from that work is "5t"
EQUATION9:
1) c + t = 49
2) 3c+5t=181
Multiply thru 1t equation by 3 to get:
1* 3c+3t= 147
Subtract 1* from 2) to get:
  2t=34
t=17 (# of trucks washed)
c=49-17= 32 (# of cars washed)
Cheers,
Stan H.