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 ..

geometry: triangles

solvers

lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584