Page 25 - Start Up Mathematics_5

6 Find the missing digits.

L TTh Th H T O L TTh Th H T O
(a) 4 ? 7 ? 9 3 (b) 3 ? 4 ? 7 0
2 8 ? 4 ? 6 – ? 8 ? 7 ? 6

+ ? 1 9 2 3 ? 1 7 1 6 1 ?
8 7 1 9 5 3

7 Aditya works as a sales manager in a firm and earns ` 92,675 in 5 months. He spends ` 550
every month on grocery and ` 675 on other expenses. He saves the rest of his salary. How
much money does Aditya save in 5 months?

Addition

We know how to add 5-digit and 6-digit numbers. Now let‘s learn to add 7-digit, 8-digit and
9-digit numbers.
Adding 7-digit, 8-digit, 9-digit, ... numbers is same as adding 5 or 6-digit numbers.

Addition (without carry over)
Remember
Example 1: Add 23,14,213 and 42,40,365 and write the
addends and the sum obtained in words. Add the ones, the tens, the
hundreds and so on.
TL L TTh Th H T O
Solution: 2 3 1 4 2 1 3

+ 4 2 4 0 3 6 5
6 5 5 4 5 7 8

So, 23,14,213 + 42,40,365 = 65,54,578.

Addends
23,14,213 → Twenty-three lakh fourteen thousand two hundred thirteen
42,40,365 → Forty-two lakh forty thousand three hundred sixty-five

Sum
65,54,578 → Sixty-five lakh fifty-four thousand five hundred seventy-eight

Example 2: Find the sum of 7,30,51,215; 1,42,35,620 and 1,25,03,152.

C TL L TTh Th H T O
Solution: 7 3 0 5 1 2 1 5

1 4 2 3 5 6 2 0
+ 1 2 5 0 3 1 5 2

9 9 7 8 9 9 8 7

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