Percentage increases and decreases, reverse percentage and simple interest worksheets (with solutions)

Three worksheets on the following: calculating the percentage of an amount, finding the simple interest paid for a loan and the rate of interest given the interest paid and the amount loaned, increasing or decreasing an amount by a given percentage and working out the percentage increase or decrease given the original and final amount and calculating the original value given the value after a percentage increase or decrease. Detailed solutions are included.