Introduction:

* Digit: Whole numbers from 0 to 9 are called digits.
* Mixed Number: The sum of the whole numbers and the fractional Numbers are called the Mixed Numbers.

like-  Noble Suggestion:- About 7 questions related to addition and subtraction in the BANK CLERICAL exams are asked. In this, 5 questions are related to the whole number and 2 questions of the Mixed Number. More questions have to be resolved in less time in the competition examinations. Therefore, for the time being, efforts should be made to solve the problems based on addition and subtraction only through mental action.

Tricks with Trickily Solved Examples

### A. Addition and Subtraction of Mixed Numbers

TRICK ⇒ complete numbers are added together and the fractions are added together. But if the sum of fractions comes in the form of a composite number then the whole number in it is added to the sum of the whole numbers.  Type-1

TRICK- If in the given question of addition the fraction with equal denominator present then the whole numbers are added together and the fractions with equal denominator are added together.  Type-2

Trick ⇒ If there are two or more such Numbers present in the question whose addition and subtraction gives the answer as ‘1’. Then, such fractions are added and subtracted simultaneously.  Type-3

Trick ⇒ If there are two or more such Numbers present in the question whose addition and subtraction gives the answer as ‘0’. Then, such fractions are added and subtracted simultaneously.  Type-4

Trick ⇒ If there are different types of fractions present in the questions related to addition and subtraction of mixed numbers, then the whole numbers are added or subtracted together and the fractions are added and subtracted together.  Type-5

Trick ⇒ In the questions based on combined numbers, when the result of addition or subtraction of whole numbers and addition or subtraction of fractions computed separately and the result of fraction becomes negative and less than 1, Then the result of whole number would be break by 1 by introducing ‘+’ sign and the Fraction will be subtracted from it.  ### B. ADDITION AND SUBTRACTION OF WHOLE NUMBERS

Trick ⇒ In the Questions based on the addition and subtraction of whole numbers. The number of units, ten, hundredths, thousand and ten thousand given in the expression are added or subtracted simultaneously with the corresponding digit. The unit number obtained from the sum of the digits of the unit is placed at the place of the unit for that expression and the remaining number is added to the sum of the tenth digit. Again, the unit number of the sum of the digits of the tenth digit is placed at the place of tens for that expression and the remaining number is added to the sum of hundreds of digits. In the end, similar actions are also continued to get the sum of the expression.

Example: 57432 + 2346 + 785 + 34 =?

Explanation:
1st step. (2 + 6 + 5 + 4) =  7 ⇒ digit of the sum of unit= 7
2nd step. (3 + 4 + 8 + 3 + ) =  9 =  digit of the sum of Tenth = 9
3rd step. (4 + 3 + 7 + ) =  5 ⇒ digit of the sum of hundredths= 5
4th step. (7 + 2 + ) =  0 ⇒ digit of the sum of Thousand = 0
5th step. (5 + ) = 6 ⇒ = digit of the sum of Tenth Thousand  = 6
So the desired sum = 60597
Type-1

TRICK ⇒ If the addition and subtraction of an expression is given to do at the same, Then the largest positive number in the expression is assumed to be the basis. If after adding or subtracting the digits of the units of the remaining numbers, if the positive number is obtained then it is added to the number of units of the number assumed, and if number is obtained then  it is subtracted to the number of units of the number assumed. If the unit number of the assumed number is small and the unit digit of negative number is large, then the unit number of the base is raised by negative number and then subtract the negative number. This type of action is also done for tens of ten, hundredths, thousand and ten thousand respectively.

Example: 75653 – 43264 + 3246 – 7535 + 78 =?

Explanation: Basis =     

1st step. (-4 + 6 – 5 + 8) = 5 ⇒  + 5 = 8,

∴ digit of unit of expression = 8

2nd step (-6 + 4 – 3 + 7) = 2 ⇒  + 2 = 7,

∴  digit of tenth of expression = 7

3rd step. (-2 + 2 – 5) = – 5 ⇒  – 5 = 1,

∴  digit of hundreds of expressions = 1

4th step. (-3 + 3 – 7) = -7 ⇒15 – 7 = 8,

∴  digit of thousand of expression = 8

last step. Digit of ten thousand of expressions = (6-4) = 2
So the desired sum = 28178.
Type-2

Trick ⇒ In the questions based on addition and subtraction If there are some numbers on the left side of ‘=’ and some numbers are on the right side of ‘=’ and (?) is with ‘+’ sign Then the signs of the numbers on the side of (?) are considered as ‘+’ to (-) and ‘-‘as the “+” symbol to perform the function of addition and subtraction.

Example: 57543 ー 2346 +? = 85432

Explanation: Base =     

1st step. (-3 + 6) = 3 ⇒  – 3 = 5,

∴ digit of unit of expression = 5

2nd step. (-4 + 4) = 0 ⇒  + 0 = 3,

∴  digit of tenth of expression = 3

3rd step. (-5 + 3) = -2 ⇒  -2 = 2.

∴  digit of hundreds of expressions = 2

4th step. (-7 + 2) = – 5 ⇒  – 5 = 0,
∴ digit of thousand of expression = 0

last step.  – 5 = 3

∴ digit of ten thousand of expression = 3

∴ ? = 30235 Ans.
Type-3

Trick ⇒ In the questions based on addition and subtraction If there are some numbers on the left side of ‘=’ and some numbers are on the right side of ‘=’ and (?) is with ‘+’ sign Then the signs of the numbers on the other side of (?) are considered as ‘+’ to (-) and ‘-‘as the “+” symbol to perform the function of addition and subtraction.

Example – 94532 – 6754 -? = 75432 – 2346

Explanation : Base = 8 13 14 13
    

1st step. (- 4-2 + 6) = 0 ⇒  + 0 = 2,

∴ digit of unit of expression = 2

2nd step (-5 -3 + 4) = -4 ⇒ (13-4) = 9

∴  digit of tenth of expression = 9

3rd step (- 7-4 + 3) = -8 ⇒ (14-8) = 6

∴  digit of hundred of expression = 6

4th step. (-6-5 + 2) = -9 ⇒ (13-9) = 4

∴  digit of thousand of expression = 4
last step (8-7) = 1

∴ digit of Ten thousand of expression = 1

∴ ? = 14692 Ans.
Type-4

Trick ⇒ If the total numbers present in the question of any addition are made of the same number of repetitions and the first, second, third, and fourth numbers are of one, two, three and four digits respectively. Then the repeating number obtained by multiplying by 4 3 2 and 1, respectively, is placed at the place of unit, ten, hundredth and thousand of sum, respectively, as well as its carry will be added to the number on left side of corresponding digit.

Example : 6666 + 666 + 66 + 6 =?
Explanation :

1st step. 4 × 6 =  4 ⇒ digit of units = 4
2nd step. 3 × 6+  =  0 ⇒ digit of the tenth = 0
3rd step. 2 × 6+  =  4 ⇒ digit of hundredths = 4
Last step. 1 × 6 +  = 7 ⇒ digit of thousandths = 7
∴ ? = 7404 Ans.
Type-5

Trick ⇒ If the total numbers present in the question of sum of decimal numbers are made of the same number of repetition and the first, second, third and fourth numbers having  one, two, three and four digits after decimal. Then the repeating number obtained by multiplying by 4 3 2 and 1, respectively, is placed at the place of unit, ten, hundredth and thousand of sum, respectively, as well as its carry will be added to the number on left side of corresponding digit. In the end, the decimal is placed after the four digits on the left side of the sum.

Example : 0.9999 + 0.999 + 0.99 + 0.9 =?

Explanation :

1st step. 9 × 1 = 9 ∴ Digit of the unit of sum = 9
2nd step. 9 × 2 =   Digit of the tenth = 8,
3rd step. 9 × 3 +  =  Digit of the Hundred of the sum = 8
4th step. 9 × 4 +  =  8 ∴ Digit of thousandths = 8
last step. Digit of ten thousand = 3

∴ ? = 3.8889 Ans.
Type-6

Before solving the questions based on the addition and subtraction of decimal numbers, the digits of decimal numbers made equal to the maximum digits after the decimal in the present numbers by placing zero (0) after decimal. After this, the action of addition and subtraction should be performed.

Example: 43.632 + 3.05 + 437.102 – 232.56 =?
Explanation: ? = 43.632 + 3.050 + 437.102 – 232.560

Base =      

1st step. (2 + 0 – 0) =  ⇒ 2 + 2 = 4

∴ Digit of unit of sum = 4

2nd step. (3 + 5-6) = 2 ⇒  + 2 = 2

∴ Digit of tenths of the sum = 2

3rd step. (6 + 0 – 5) = 1 ⇒  + 1 = 2

∴ Digit of hundreds of sums = 2

4th step. (3 + 3 – 2) = 4 ⇒  + 4 =  +1

∴ Digit of thousandths of the sum = 1

5th step. (4-3) = 1 ⇒  +  + 1 = 5

∴ Digit of ten thousand of sum = 5

last step. Digit of lakhs of sum = (4 – 2) = 2
∴ ? = 251.224 Ans.