# Mathematical Shortcuts For All Exams

To check addition is correct : Add up the single digits of each individual number in the sum, until you are left with a single digit.

-Add these single digits together until you are, once again, left with a single digit.

-Do the same with the total these figures should be the same

Example: 7745 + 3289 = 11034

7+7+4+5 = 23 2+3 = 5

3+2+8+9 = 22 2+2 = 4

9

1+1+0+3+4 = 9

Example : 4320 – 1978 = 2342

1978+2342 = 4320

To check multiplication is correct : Divide the answer by one of the numbers being multiplied.

Example : 27 x 19 = 513

513 ÷ 19 = 27

To check division is correct : Multiply the answer by the number you originally divided by and this answer should be the same as the original number being divided.

Example: 798 ÷ 14 = 57

57 x 14 = 798

(193)