Which of these examples is an error of addition by one?
a. 27,465 +52,534 = 79,899
b. 63,528 + 24,361 = 87,889
c. 51,824 + 48,165 = 99,989
d. 35,246 + 43,732 = 78,978

The correct answer is:

A. 27,465 +52,534 = 79,899

Step-by-step explanation:

Given are the options for addition

We have to check each addition one by one

So,

A. 27,465 +52,534 = 79,899

This option is the example of error of addition by one. The answer should have been 79,999. Hence there is an error in addition ..

Hence, option a: 27,465 +52,534 = 79,899  is the correct answer ..

answer: the answer is 127 degrees