The directions for mixing an insect spray say to use 2 7/8 ounces of chemical in each gallon of water. how many ounces of chemical should be mixed with 3 2/3 gallons of water? first, estimate the answer to the application problem. then find the exact answer.

Estimate : 
2 7/8 ounces ≈ 3 ounces
3 2/3 ounces ≈ 4 ounces 

1 gallon needs about 3 ounces of chemical
4 gallons needs about 3 x 4 = 12 ounces of chemical



Actual:

1 gallon = 2 7/8 ounces of chemical
3 2/3 gallon = 2 7/8 x 3 2/3 ounces of chemical.
[Assuming you can use the calculator to compute]
3 2/3 gallon = 10 13/24 ounces of chemical.