Answer:
68
Step-by-step explanation:
Lets first find the quantity of tape the computing center is purchasing/month.
3/5 Of their 1600 dollar spending is on the heavy duty tapes, meaning they are spending 960 dollars/month on heavy duty tape, if we divide that by the original price, 40, it will give us the original quantity of heavy tape they are purchasing, 24/month.
The other 2/5 of their money, 640 dollars, are spent on regular tape, meaning they purchase 20 rolls of regular tape/month.
Given they are purchasing 24 rolls of heavy tape and 20 rolls of regular tape every month, we can simply multiple those by the new prices and sum the results.
24*38=912
20*31=620
912+620=1532
Then to find the money they are saving we subtract the new price from the original price.
1600-1532=68