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Two customers went to a post office. first customer paid $12 for 14 and 5 envelopes the second paid 24.80 for 10 postcards and 15 envelopes. what is cost of each envelope?

If log_3(x)=4.5 and log_3(y)=3, what is log_3(x^2/y)? a. 3b. 6.75c. 6d. 1.5

If x varies directly as y, and x = 7.5 when y = 10, find x when y = 4