9514 1404 393
Answer:
- 64 weeks
- 4 months
Explanation:
1. Let y represent gallons in the tank, and x represent number of weeks.
tank 1
y = 256 -3x . . . . . starts with 256 gallons, loses 3 per week
tank 2
y = 384 -5x . . . . . starts with 384 gallons, loses 5 per week
The amounts in the tanks will be equal when the y-values are equal.
y = y
256 -3x = 384 -5x
2x = 128 . . . . add 5x-256
x = 64 . . . . . . divide by 2
The amount of water in the two tanks will be equal after 64 weeks.
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2. Let s and f represent the total cost of membership at Silver Gym and Fit Factor, respectively. Let x represent the number of months of membership.
s = 25 +30x
f = 65 +20x
The costs are the same when s=f.
s = f
25 +30x = 65 +20x
10x = 40 . . . . . . subtract 25 +20x
x = 4 . . . . . . . . . divide by 10
The two memberships will be the same price after 4 months.