Carey is trying to decide between two guitars. the first had an original price of $160, but is on sale for $100. the second had an original price of $250, but is on sale for $150. which guitar has a greater percent change in price?

The second guitar is the answer because it has a lower amount than the first but not by alot

The original prices of the guitars are 100%. Example: for the $160 guitar, $160 would be 100% of the price. The new price is $100. The guitar went down $160-$100=$60. 60/160 = 0.375. Convert that into a percentage. 0.375 = 37.5%. Guitar number one has decreased by 37.5%. 
Guitar number 2: $250 = 100%. It went down $250-$150=$100. 100/250 = 0.40. Convert to percentage. 0.40 = 40%. 
Guitar 1 had a decrease of 37.5% in price
Guitar 2 had a decrease of 40% in price.
Hope this helps!

Idon’t know this and this isn’t middle school work

270 books in each shelves