AP State Syllabus AP Board 6th Class Maths Solutions Chapter 6 Basic Arithmetic Unit Exercise Textbook Questions and Answers.
AP State Syllabus 6th Class Maths Solutions 6th Lesson Basic Arithmetic Unit Exercise
Question 1.
Draw a four sided closed figure and divide it into some number of equal parts. Shade the figure with any colour so that the ratio of shaded parts to unshaded parts is 1 : 3.
Answer:
Given ratio of shaded parts: unshaded parts = 1 : 3
Total parts of a closed figure = 1 + 3 = 4
Consider a four sided closed figure square.
Divide it into 4 parts and shade one part.
Now, from the figure, shaded parts : unshaded parts = 1 : 3
Question 2.
Ramu spent \(\frac{2}{5}\)th of his money on a story book. Find the ratio of money spent to the money with him at present.
Answer:
Given money spent on story book = \(\frac{2}{5}\) th of his money.
That means from total 5 parts of money he spent 2 parts of money on story book. Then, out of 5 parts remaining parts of money with him is 3 parts.
So, ratio of money spent to the money with him at present
= parts of money spent : parts of money at him = 2 : 3
Question 3.
Divide Rs. 72,000 between Kesav and David in the ratio of 5 : 4.
Answer:
Amount to be divided = Rs. 72,000
Ratio of Kesav and David’s Shares = 5 : 4
Total shares = 5 + 4 = 9
Kesav’s share = \(\frac{5}{9}\) of 72000
\(\frac{5}{9}\) × 72,000 = 40,000/-
David’s share = \(\frac{4}{9}\) of 72,000
\(\frac{4}{9}\) × 72,000 = 32,000/-
Question 4.
The income of Kumar for 3 months is Rs. 15,000. If he earns the same amount for a month,
a) How much will he earn in 5 months?
b) In how many months, will he earn Rs. 95,000?
Answer:
Given Kumar’s 3 months income = Rs. 15,000
Kumar’s one month income = 15,000 ÷ 3
= \(\frac{15000}{3}\) = Rs. 5000
a) Kumar’s one month income = Rs. 5000
Kumar’s 5 months income = 5 × 5000 = Rs. 25,000
b) Time taken by Kumar to earn Rs. 5000 = 1 month
Time taken by Kumar to earn Rs. 95,000 = 95,000 ÷ 5000
= \(\frac{15000}{3}\) = 19 months = 1 year 7 months.
Question 5.
The cost of 16 chairs is Rs. 4,800. Find the number of chairs that can be purchased for Rs. 6,600.
Answer:
Cost of 16 chairs = Rs. 4800
Number of chairs that can be pruchased for Rs. 6600 = x (say)
∴ 16 : 4800 : : x : 6600
So, 16 x 6600 = 4800 x x
x = \(\frac{16 \times 6600}{4800}\) = 22 chairs
(OR)
Given cost of 16 chairs = Rs. 4800
Cost of one chair = 4800 ÷ 16
= \(\frac{4800}{3}\) = Rs. 300
Number of chairs can purchased for Rs. 6600 = 6600 ÷ cost of one chair
= 6600 ÷ 300
= \(\frac{6600}{300}\) = 22 chairs
Question 6.
What percentage of numbers from 1 to 30 has 1 or 9 in the unit’s digit?
Answer:
Total number from 1 to 30 = 30
Numbers ending with 1 or 9 are 1, 9,11, 19, 21, 29 = 6 numbers
Ratio = 6 : 30 = \(\frac{6}{30}\) = \(\frac{1}{5}\)
Percentage = \(\frac{1}{5}\) × 100% = 20%
Question 7.
In a college, 63% of students are less than 20 years of age. The number of students more than 20 years of age is — of number of students of 20 years of age which is 42. What is the total number of students in the college?
Answer:
Let the total number of students be x.
Then, number of students more than 20 years of age = (100 – 63)% of x
= 37% of x
Then, 37% of x = 42 + \(\frac{2}{3}\) of 48
\(\frac{37}{100}\) × x = 74
∴ x = 74 × \(\frac{100}{37}\) = 200