Answer:
Result = 9b/25 or 36b/100
Explanation:
The number is b
step 1
b is decreased by 40%
value of 40% of b = 40/100 *b = 4b/10
New value after this change = b - 40% decreased value of b = b -4b/10
= (10b-4b)/10 = 6b/10
Step 2 The new value obtained is again decreased by 40%
value of 40% number found in step 1 = 40% of value found in step 1
value of 40% number found in step 1 = 40/100 * 6b/10 = 24b/100
This value (24b/100) is subtracted from value found in step 1(6b/10) as given that value obtained is decreased by 40%
new value found after 40% decrease = 6b/10 - 24b/100
new value found after 40% decrease = 60b/100 - 24b/100= 36b/100
new value found after 40% decrease = 36b/100 = 9b/25
Thus, the result of b is decreased by 40% and decreased again by 40% is 9b/25