Let $S=15.247 \div 14.85 + 18.1$ . How much larger is if you round each of these numbers to the nearest ten before calculating $S$ than if you round each to the nearest whole number?
Thank you in advance!
I also have one more question:
Let n be a positive integer and a, b be invertible integers modulo n such that a = b^-1 (mod n). What is the remainder when a*b is divided by n?
Rounded to nearest 10, we have
(20 / 10 ) + 20 =
2 + 20 =
22
Rounded to nearest whole number
( 15 / 15) + 18 =
1 + 18 =
19
22 - 19 = 3
