1. As per the 2001 census report, our population was 1,027, 015, 247. If 531, 277, 078 were males, how many were females?

Total population       = 1, 027, 015, 247

Number of males     = 531, 277, 078

Number of females   = [1, 027, 015, 247 - 531, 277, 078] = 495,738,169

2. As per the 2001 census report, out population was 1,027, 015, 247. The total number of literate in our country in 2001 was 566, 714, 995. If 226, 745, 947 were women how many men were literate then?

Number of literate in our country  = 566, 714, 995

Number of women  literate  = 226, 745, 947

Number of men  literate  = [566, 714, 995 - 226, 745, 947] = 339, 969, 048

3. As per the 2001 census report, out population was 1,027, 015, 247. Male senior citizens (above 65 years) were 25, 281, 756 and females and 24, 585, 317. How many senior citizens in all were there in the country then?

Number of male senior citizen = 25, 281, 256

Number of female senior citizen = 24, 585, 317

Total number of senior citizen = [25, 281, 756 + 24, 585, 317] = 49, 867, 073

4. The economy fare from Delhi to London is Rs. 38, 650 what will the fare be for a group of 36 holidays makers?

The economy fare from Delhi to London   =  38650

Number of holiday markers   =  36

Total fare need for a group of 36 holiday markers  =  38, 650 × 36 = 1391400

Step for multiplication.

5. The distance between Chennai and Trichy is 352 km. If Mr. Kumar's car gives 14 km to every litre of petrol, how many liters of petrol will Mr. kumar use to go to Trichy? (give your answer to the nearest litre)

Total distance to be covered  =  352 km

Distance covered by car for 1 litre of petrol  = 14 km

Quantity of petrol in litre, which is needed to cover 352km  = 352 ÷ 14 = 25 litre

Steps for 353 ÷ 14

6. 2040 m of cable are cut into 24m lengths. How many pieces of cable will that be?

Total length of cable  =  2040 m

Length of one piece   = 24  m

Number of pieces  = 2040 ÷ 24 = 85

Steps for 2040 ÷ 24

7. One 165 l refrigerator costs Rs. 8, 989. A hotel buys 252 refrigerators. How much money did they spend on refrigerators?

Cost of one refrigerator  = 8, 989

Cost of 252 refrigerators = 8, 989 × 252

                                        = Rs. 2, 265, 228

Steps for 8989 × 252

8. The cost of printing one brochure was Rs. 52. If 550 brochure were printed, what would have been the total cost of printing the brochures?

Cost of printing one brochure = Rs, 52

Cost of printing 550 brochure = 550 × 52

                                                = Rs. 28600

Steps for 550 × 52

9. What is the easy method of multiplying a number with 10,100 and 1,000?

For multiplying a number with 10 or 100 or 1000, simply place 0 to the right end of the number . When a number multiplied by 10, 100 and 1000, we can place one zero, two zeros, and three zeros at the right end of number.

10. Multiply the number 491 by  i) 10  (ii) 100  and  (iii) 1000.

         (i) 491  × 10   = 4910

         (ii) 491 × 100  = 49100

        (iii) 491 × 1000 = 491000

11. Solve the following.

a. 23 × 10

23 × 10  = 230, place one zero to the right end of number.

b. 345 × 100

345 × 100 = 34500, place two zeros at the right end of number.

c. 41 × 1000

41 × 1000 = 41000, place 3 zeros at the right end of number.

12. Try to solve quickly the following.

a. 56  × 400

     (56 × 4) × 100 = 22400          400 = 4 × 100

b. 190 × 50

     (190 × 5 ) × 10 = 9500            50 = 5 × 10

c. 83 × 300

       83 × 300

       = (83 × 3) × 100

       = 24900                                300 = 3 × 100 

13. Use quick method for multiplication by 5,25 and 50 solve the following.

a. 34 × 25

34 ×  25   = (34 × 100) ÷ 4          25  = 100 ÷ 4                                    

                = 3400 ÷ 4

                = 850

b. 112 × 50

112   × 50   = (112 × 100) ÷ 2              50 = 100 ÷ 2

                  = 11,200 ÷ 2

                  = 5600

c. 678 × 50

(678 × 100) ÷ 2           50  = 100 ÷ 2

=  67800 ÷ 2

= 33900

14. Use the quick and easy method to solve the below, where divisors are numbers close to 100.

a. 45 × 99

45 × (100 - 1)                        99 = 100 -1

        = 45 × 100  - 45

        = 4500 - 45

        = 4455

b. 56 × 101

56 × (100 + 1)                    101 = 100 + 1

        = 56 × 100 + 56

        = 5600 + 56

        = 5656

c. 112 × 98

112 × (100 - 2)                             98 = 100 - 2

        = 112 × 100 - 112 × 2

        = 11200 - 224

        = 10976

d. 67 × 102

67 × 102                                   102 = 100 + 2  

         = 67 × (100 + 2)

         = 67 × 100 + 67 × 2

         = 6700 + 134

         = 6834                                                                                          

15. Do the following as fast as you can.

a. 34 × 20

(34 × 2 ) × 10                    20 = 10 × 2

         = 68 × 10

         = 680

b. 45 × 20

45 × 20

         = (45 × 2) × 10               20 = 10 × 2

         = 90 × 10

         = 900

c. 36 × 20

36 × 20  =  (36 × 2) × 10           20 = 10 × 2

              = 72 × 10

              = 720

16. Do the following in minimum steps.

a. 19 × 162 

b. 16 × 125