Mr. Zhang bought a house in early 2008 with a loan of 200000 yuan for 10 years (120 months) and a monthly interest rate of 5%. He paid off the principal and interest at the end of the 10th year. How much is the monthly repayment amount of Mr. Zhang

Mr. Zhang bought a house in early 2008 with a loan of 200000 yuan for 10 years (120 months) and a monthly interest rate of 5%. He paid off the principal and interest at the end of the 10th year. How much is the monthly repayment amount of Mr. Zhang

Simple interest or compound interest?

A practical problem in sequence (High School Mathematics) p137
1) The total area of the existing houses in a certain place is a square meter, of which the old houses to be demolished account for half. The local authorities decided to demolish a certain number of old houses every year, and still build new houses at a housing growth rate of 10%
(1) If 10 years later, the total housing area in this area will double that at present, what is the total area X of the old housing to be demolished every year? (1.1 ^ 10 is taken as 2.6 in calculation)
(2) What is the percentage of the total area of old houses that have not been demolished in 10 years?

(1) The total housing area is 1.1a-x (M2) in one year, 1.1 (1.1a-x) - x = 1.1 ^ 2a-1.1x-x (M2) in two years and 1.1 (1.1 ^ 2a-1.1x-x) - x = 1.1 ^ 3a-1.1 ^ 2x-1.1x-x (M2) in three years In 10 years, the total housing area is 1.1 ^ 10a-1.1 ^ 9x-1

High school mathematics algebra problems
It is known that a, B, C are real numbers which are not equal to each other, B, a, C are equal difference series, and a, B, C are equal ratio series. Find the common ratio of the equal ratio series

If b.a.c is an arithmetic sequence, then 2A = B + C, then C = 2a-b
a. If B C. is an equal ratio sequence, then B ^ 2 = AC, then B ^ 2 = a (2a-b)
2A ^ 2-ab-b ^ 2 = 0
(2a + b) (a-b) = 0, because a is not equal to B
So B = - 2A
So the common ratio q = B / a = - 2A / a = - 2