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alex41 [277]
3 years ago
5

A commuter has $345 in his commuter savings account. This account changes by -$15 each week he buys a ticket. In one time period

, the account changed by -$240.
a. For how many weeks did the commuter buy tickets?
_________________________________________________________________________
b. How much must he add to his account if he wants to have 20 weeks’ worth of tickets in his account? ________________________________________________________
Mathematics
1 answer:
Roman55 [17]3 years ago
7 0

Answer:

A.16 weeks

B. $195

Step-by-step explanation:

A.

345-15x=345-240

345-15x=105

15x=240

x=16

B.

345-240=105

20x15=300

105+x=300

x=195

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We can cancel the y² and 4 from both sides. We can also subtract 4y from both sides. This leaves us with:

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