Divide the difference of 18 and 3 by the sum of 1 and 2 as an expression

Can you simplify 4/7? 24 points will be awarded!

Imogene invested $8,000 in a bank account that pays 8 percent simple interest at the end of each year. her friend invested the same amount in stocks where the growth of the investment is represented as 2,000 times the square root of 2 less than the time lapsed in years. if y1 and y2 represent the amount earned in dollars and t is the time lapsed in years, which system of equations correctly represents the situation?

Daniel bought a computer game for $25 and later sold it to thomas for a 40% profit. how much did daniel sell the computer game for?