Jake can wash his car with 1 bottle of car wash soap 4 times.  If each bottle costs $4.00, and he washes his car once a week for 20 weeks, how much does he spend on car soap?
1 bottle of soap will last for 4 washes and he needs enough bottles for 20 weeks so 20/4 = <<20/4=5>>5 bottles
Each bottle cost $4.00 and he needs 5 bottles so he will spend $4*5 = $<<4*5=20.00>>20.00 on car soap
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