What is the answer to this problem

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

Billie holiday sells children's clothing for sara vaughn's toddler shop. baby blankets sell for $29.99 after a markup rate based on cost of 109%. find the cost and the markup.

Find the pattern and use inductive reasoning to predict the next number in the sequence 100, 120, 60, 80, 40,