Samacheer Kalvi 3rd Standard Maths Book Solutions Term 3 Chapter 7 Information Processing
Quick ways of adding (Text Book Page No. 49):
Answer:
Exercise (Text Book Page No. 50):
Find the sum of
i) 5 + 1 + 5 + 9
Answer:
5 + 5 = 10
9 + 1 = 10
Hence the sum = 10 + 10 = 20
ii) 2 + 5 + 5 + 7 + 1
Answer:
2 + 7 + 1 = 10
5 + 5 = 10
Hence the sum = 10 + 10 = 20
iii) 3 + 6 + 1 + 2 + 8
Answer:
3 + 6 + 1 = 10
8 + 2 = 10
Hence the sum = 10 + 10 = 20
Add the given big numbers using the above method (Text Book Page No. 51):
Question 1.
Answer:
543 = 500 + 40 + 3
210 = 200 + 10
Question 2.
Answer:
298 = 200 + 90 + 8
501 = 500 + 1
Question 3.
Answer:
798 = 700 + 90 + 8
654 = 600 + 50 + 4
Question 4.
Answer:
348 = 300 + 40 + 8
681 = 600 + 80 + 1
Question 5.
Answer:
543 = 500 + 40 + 3
218 = 200 + 10 + 8
Question 6.
Answer:
716 = 700 + 10 + 6
540 = 500 + 40 + 0
Quick ways of subtracting (Text Book Page No. 52):
Answer:
Subtract the given numbers using the above method (Text Book Page No. 53):
Question 1.
Answer:
Question 2.
Answer:
Question 3.
Answer:
Question 4.
Answer:
Question 5.
Answer:
Question 6.
Answer:
Question 7.
Answer:
Question 8.
Answer:
Question 9.
Answer:
Mental Arithmetic (Text Book Page No. 54):
Able to add and subtract single digit numbers and two digit numbers mentally:
Question 1.
In a tree planting ceremony, 6 coconut saplings and 5 neem saplings are planted. Find the total number of saplings planted.
Answer:
6 + 5 = 11
Question 2.
There are 5 tender coconuts in a tree. If they pick 3 tender coconuts, then find the remaining tender coconuts?
Answer:
5 – 3 = 2
Question 3.
46 boys and 27 girls visited a park on Sunday. Find the total number of boys and girls who visited the park?
Answer:
46 + 27 = 73
Question 4.
50 pens are in a box. Out of which, 34 pens are given to the students. Find the number of pens left?
Answer:
50 – 34 = 16
Question 5.
70 balls are given to 7 persons. How many balls are given to each person?
Answer:
70 ÷ 7 = 10 [10 × 7 = 70]
Question 6.
8 books can be arranged in a row. In how many rows can 48 books be arranged?
Answer:
48 ÷ 8 = 6 [8 × 6 = 48]
Question 7.
10 pens can be kept in a box. How many boxes are needed to keep 100 pens?
Answer:
100 ÷ 10 = 10
3rd Standard Maths Guide Information Processing Additional Questions and Answers
Question 1.
Find the sum of
(i) 7 + 7 + 3 + 3
Answer:
7 + 3 = 10 and
7 + 3 = 10
Hence the sum of the number = 10 + 10 = 20
(ii) 6 + 4 + 4 + 6
Answer:
6 + 4 = 10 and
4 + 6 = 10
Hence the sum of the number = 10 + 10 = 20
Question 2.
Add
Answer:
Question 3.
Add
Answer:
Question 4.
Subtract
Answer:
Question 5.
Subtract
Answer:
