A number is first decreased by 40% and then again decreased by 60%. Find the percentage increase or decrease in the whole sum...please tell quickly

It is decreased by 76 percent.

Step-by-step explanation:

The key skills are percentage and multiplication with percentages.

You first have to get a variable. Let's use the letter o as a variable (o For orginial cost). Then we have to find out how much it is when o is decreased by 40 percent. 100% (or the whole) - 40% is 60%. Therefore, with a 40 percent decrease, It would be 60% of o, or 0.6o. Then, if it decreases by 60 percent, the final number would be 100% - 60 % or 40% of 0.6o. This means itbwould be 0.4 × 0.6o which is 0.24o0.24o means that o is 24 percent of its orginial number, which is 100% - 24% or a 76 percent decrease.

Hope you understood and have a nice day!