In this I assumed the expression to be
X + 9 = 2X (X is the amt)
At 27 she earned 25125
At 63 we want to know the cost
As it doubles after 9 years I considered the multiples of 9
2X = 225125 and then as per this pattern: 27 36 45 54 63 I did
2X = 225125*5
which gives 25125 * 5 *2 = D
In this am i allowed to substitute any no. Wud the ans in all the cases be the same?
How to solve these two
On solving I got
(X-1)(5-1) (3-1)(X-2)
(X-1)4 (2)(X-2)