1. 7 gallons of shampoo will last 5 weeks and 1/4 of another week.
2. 16 Gallons of shampoo will last 12 weeks.
Work Shown
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0.75 (How much per gallon) × 7 (Gallon of shampoo) = 5.25 (Weeks
0.75 × 16 (How much gallons for 12 weeks) = 12 (Weeks.)
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