A oweth to B ,1200 to be paid in 6 yeares, in 12 equal payments, viz. at the end of each halfe yeare ,100. They agree to cleare this debt in 3 yeares, in 6 equall payments, viz. at the end of each halfe yeare, one payment. The Question is, what each payment ought to be, reckoning interest after the rate of 10 per cent per Ann. and int. upon int.?