Lesson 4

Lesson4

MULTIPLICATION OF 12 TO 19
MULTIPLICATION BY 12:
The method is exactly the same as in the case of 11 except that you double each number before adding the
right neighbour.
Step1 Prifix 0 before multiplicand
step2: Multiply last digit by 2 and write it at extreme right take carry if there is
Step3: Double and add the right neighbour with carry in step first repeat this upto the first
digit ie till 0
. 1234 x12= 01234x12 =
Here 2 multiply by 4 write 8 at extreme right . ...... 8
Double 3 and add to 4 and write before...8,6+4=10 here we write 0 before 8 and take 1 carry
.....08
Double 2 and add to 3 and add carry1 and write before 08 ,4 +3 +1 =8 .....808
Double 1and add to 2 and write before ...708, 2+ 2 =4 ....4808
Double 0 and add to 1 and write before .708 0+1=1 14808
14808 is our required answer

MULTIPLICATION FROM 13 TO 19:

The method is exactly the same as in the case of 12 except that you treble each degit before add in the
right neighbour, in the case of multiplication of 13 .We would quadruple (i.e. multiply by 4) and then add
the right neighbour, in the case of multiplication of 14 .In case of 19 we would multiply by 9 and then add
the right neighbour
39942 X 13 = ? 039942x13=
2x3 =6 ............ 6
4x3+2 =14 ...........46
9x3+4+1 =32 ...........246
9x3+9+3=39 ..........9246
3x3+9+3=21 ........19246
0x3+3+2=5 519246
519246 is our required answer.
34x17 =? 034x17
4x7 =28 ........8
3x7+4+2 =27 .....78
0x7 +3+2=5 578
578 is our required answer.
Now try these examples
1) 39942 X 13 = ? (2) 43285 X 14 = ?
2331 21132
039942 X 13 043285 X 14
519246 605990
(3) 58265 X 15 = ? (4) 36987 X 16 = ?
34132 25654
058265 X 15 036987 X 16
873975 591792
(5) 69873 X 17 = ? (6) 96325 X 18 = ?
57652 85224
069873 X 17 096325 X 18
1187841 1733850
(7) 74125 X 19 = ?
73124
074125 X 19
Practice Test
24678 x 13= 246x13x 15= 89x19 x18=
98745 x14= 987 x19 = 266x16=
98745 x17= 8745x 12 = 3435 x12=
Check your answer with the help of calculator