Answer:
28% decrease
Explanation:
If we decrease by 60%, we are keeping 100-60 = 40%
Let x be the original amount
decrease by 60% = keep 40%
.40 x
If we increase by 80%, we are keeping 100+80 = 180%
(.40x) * 180%
.40x * 1.80
.72x
Take .72 times the original amount
100 - .72 = 28
It decreased 28 %