SCERT AP 7th Class Maths Solutions Pdf Chapter 2 Fractions, Decimals and Rational Numbers Ex 2.2 Textbook Exercise Questions and Answers.
AP State Syllabus 7th Class Maths Solutions 2nd Lesson Fractions, Decimals and Rational Numbers Exercise 2.2
Question 1.
Find the product of the following.
(i) 23.4 × 6
Answer:
= \(\frac{234}{10} \times \frac{6}{1}\)
= \(\frac{1404}{10}\)
∴ 23.4 × 6 = 140.4
(ii) 681.25 × 9
Answer:
681.25 × 9
= \(\frac{68125}{100} \times \frac{9}{1}\)
= \(\frac{68125 \times 9}{100}\)
= \(\frac{613125}{100}\)
∴ 681.25 × 9
= 6131.25
(iii) 53.29 × 14
Answer:
53.29 × 14
= \(\frac{5329}{100} \times \frac{14}{1}\)
= \(\frac{74606}{100}\)
∴ 53.29 × 14
= 746.06
(iv) 8 × 2.52
Answer:
8 × 2.52
= 8 × \(\frac{252}{100}\)
= \(\frac{8 \times 252}{100}\)
= \(\frac{2016}{100}\)
∴ 8 × 2.52 = 20.16
(v) 25 × 2.013
Answer:
25 × 2.013
= 25 × \(\frac{2013}{1000}\)
= \(\frac{25 \times 2013}{1000}\)
= \(\frac{50325}{1000}\)
∴ 25 × 2.013 = 50.325
Question 2.
Fill the blanks in the table.
Answer:
Multiplications | Product |
36.21 × 10 | 362.1 |
23.104 × 100 | 2310.4 |
6.24 × 1000 | 6240.0 |
0.02105 × 1000 | 21.05 |
9.234 × 100 | 923.4 |
1.3004 × 1000 | 1300.4 |
5.9001 × 10 | 59.001 |
Question 3.
Find the product.
(i) 5.1 × 8.1
Answer:
= \(\frac{51}{10} \times \frac{81}{10}\)
= \(\frac{51 \times 81}{10 \times 10}\)
= \(\frac{4131}{100}\)
∴ 5.1 × 8.1 = 41.31
(ii) 63.205 × 0.27
Answer:
63.205 × 0.27
= \(\frac{63205}{1000} \times \frac{27}{100}\)
= \(\frac{63205 \times 27}{1000 \times 100}\)
= \(\frac{1706535}{100000}\)
∴ 63.205 × 0.27 = 17.06535
(iii) 1.321 × 0.9
Answer:
1.321 × 0.9
= \(\frac{1321}{1000} \times \frac{9}{10}\)
= \(\frac{1321 \times 9}{1000 \times 10}\)
= \(\frac{11889}{10000}\)
∴ 1.321 × 0.9 = 1.1889
(iv) 6.51 × 0.99
Answer:
6.51 × 0.99
= \(\frac{651}{100} \times \frac{99}{100}\)
= \(\frac{651 \times 99}{100 \times 100}\)
= \(\frac{64449}{10000}\)
∴ 6.51 × 0.99 = 6.4449
(v) 837.6 × 0.006
Answer:
837.6 × 0.006
= \(\frac{8376}{10} \times \frac{6}{1000}\)
= \(\frac{8376 \times 6}{10 \times 1000}\)
= \(\frac{50256}{10000}\)
∴ 837.6 × 0.006 = 5.0256
Question 4.
Rithesh reads a book for 2.5 hours everyday. If he reads the entire book in a week, then how many hours all together are required for him to read the book ?
Answer:
Given, time taken to read a book per day = 2.5 hours.
Time taken to read entire book in a week (one week = 7 days)
= 2.5 × 7 days
= \(\frac{25}{10}\) × 7
= \(\frac{175}{10}\)
∴ Time taken to read entire book = 17.5 hours.
Question 5.
Find the area of the rectangle whose length and breadth are 5.3 cm, 2.7 cm respectively.
Answer:
Given length of the rectangle l = 5.3 cm
Breadth of the rectangle b = 2.7 cm
Area of the rectangle = l × b
= 5.3 × 2.7
= \(\frac{53}{10} \times \frac{27}{10}\)
= \(\frac{53 \times 27}{10 \times 10}\)
∴ Area of the rectangle = \(\frac{1431}{100}\)
= 14.31 sq.cm
Question 6.
If the cost of each cement bag is ₹ 326.50, then find the cost of 24 bags of cement.
Answer:
Given, cost of each cement bag
= ₹ 326.50
Cost of 24 cement bags
= 326.50 × 24
= \(\frac{32650}{100}\) × 24
= \(\frac{32650 \times 24}{100}\)
= \(\frac{783600}{100}\)
∴ Cost of 24 cement bags = ₹ 7,836.
Question 7.
Dharmika purchased chudidhar material of 1.40 m at the rate of 7152.5 pet irtetre. Find the amount to be paid.
Answer:
Given cost of one meter chudidhar material = 7152.50
Cost of 1.40 meter chudidhar material = 152.50 × 1.40
= \(\frac{15250}{100} \times \frac{140}{100}\)
= \(\frac{15250 \times 140}{100 \times 100}\)
= \(\frac{2135000}{10000}\)
∴ Cost of 1.40 meter chudidhar material = ₹ 213.50
Question 8.
If a picture chart costs 74.25. Amrutha wants to buy 16 charts to make an album. How much money does she has to pay ?
Answer:
Given, cost of one picture chart = ₹ 4.25
Cost of 16 charts = 4.25 × 16
= \(\frac{425}{100}\) × 16
= \(\frac{425 \times 16}{100}\)
∴ Cost of 16 charts to make album = \(\frac{6800}{100}\) = ₹ 68