Apositive number "a" or the same number "a" increased by 50% and then decreased by 50% of the result? how bigger is the number?

Agreeting card company can produce a box of cards for $7.50. if the initial investment by the company was $50,000, how many boxes of cards must be produced before the average cost per box falls to $10.50?

One month, a music site observed that 60% of the people who downloaded songs from its site downloaded q sam's latest single. the equation below represents this information, where x represents the total number of people who ddownloaded songs from the site that month: x = 0.6x + 384 how many people who downloaded songs from the site that month downloaded q sam's latest single?

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way