Gabriel spent 40% of his money on a school bag. He spent 2/5 of the remainder on some stationeries. What percentage of his money was left?

After spending 40% on school bag, 60% would be left,

but he then spends 2/5 of that on stationary.
2/5 of 60% is 24%,
leaving him with 36% of the original money.

e.g. suppose he has $100, spends 40% or $40 on bag
leaves him with $60
spends (2/5) of $60 or $24 , so he has $36 left
which is 36% of the original $100