Charlotte owes $8,100 on her credit cancer. The bank charges a monthly interest rate of 1.6%. If Charlotte wants to pay off her credit card using equal monthly payments over the next 20 months, what would the monthly payment be, to the nearest dollar?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.