First membership will be best for jerry to join the gym for less than 13 days.
Given, Jerry wants to get a new gym membership.
One membership costs $40 and $10 for each class he attends.
The other membership costs $170 and he can attend an unlimited amount of classes.
we have to find for what time interval First membership be the best plan for Jerry to join the gym membership.
Let Jerry attends x number of classes,
Cost of gym in the first membership,
Total Cost = 40 + 10x
Now, Cost of gym in the second membership,
Total Cost = 170
Now, the cost in first membership should be less than in second membership
40 + 10x < 170
10x < 170 - 40
10x < 130
x < 13
So, for less than 13 days the cost of first membership will be less than second membership.
Hence, for less than 13 days the cost of first membership will be less than second membership.
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