Ariverboat travels 48 km downstream in 2 hours. it travels 60 km upstream in 3 hours. find the speed of the boat and the speed of the stream.

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

William invested $5000 in an account that earns 3.8% interest, compounded annually. the formula for compound interest is a(t) = p(1 + i)t. how much did william have in the account after 6 years? (apex)

Asmall business produces and sells balls. the fixed costs are $20 and each ball costs $4.32 to produce. each ball sells for $8.32. write the equations for the total cost, c, and the revenue, r, then use the graphing method to determine how many balls must be sold to break even.