Question

divide 21 into two parts in such a way that 10 times of one part is 1 more than 9 times of the other

Answer 1

Let the two parts be x and y

So, x + y = 21 ----(1)

A condition is given.So making it an equation we get,
10x = 9y + 1
10x - 9y = 1 ------(2)

Equating (1) and (2) we get
19y = 209
y = 11

Plugging the value of y = 11 in (1),
x + 11 = 21
x = 10

So the required two parts are 10 and 11

Hope This Helps You!