NCERT Solution Exercise 1.2 – part2 Question 5 to 9
Question (5) Find the difference between the greatest and the least number that can be written using the digits 6, 2, 7, 4, 3 each only once.
Solution
Given digits are 6, 2, 7, 4, and 3
Thus the greatest number writing each digit only once = 76,432 (Seventy six thousand four hundred thirty two)
And, the smallest number by writing each digit only once = 23,467 (Twenty three thousand six hundred sixty seven)
Now, the difference between the greatest and smallest number = The greatest number – The smallest number
= 76,432 – 23,467
= 52,965 (Fifty two thousand nine hundred sixty five)
Thus, the difference between the greatest and smallest number = 52,965 Answer
Question (6) A machine, on an average, manufactures 2,825 screws a day. How many screws did it produce in the month of January 2006?
Solution
Given,
Number of screws manufactured per day = 2,825 (Two hundred eight hundred twenty five)
Thus total number of screws manufactured in January 2006 = ?
Number of days in the month of January = 31
Therefore, total number of screws manufactured in January i.e. in 31 days
= Number of screws manufactured in 1 day × 31
= 2,825 × 31
= 87,575 (Eighty seven thousand five hundred seventy five)
Thus, number of screws manufactured in January 2006= 87,575 Answer
Question (7) A merchant had Rs 78,592 with her. She placed an order for purchasing 40 radio sets at Rs 1200 each. How much money will remain with her after the purchase?
Solution
Given,
Given,
Money merchant had = Rs 78,592 (Seventy eight thousand five hundred ninety two)
Price of one radio = Rs 1,200 (One thousand two hundred)
Total number of radio ordered = 40
Thus, money will remain after the purchase of radio = ?
Total price of radio = Price of one radio × 40
= Rs 1,200 × 40
= 48,000 (forty eight thousand)
Total price of radio ordered by the merchant = 48,000 (forty eight thousand)
Thus, money will remain with merchant after purchasing of radio
= Total money the merchant had – Price of total radio
= Rs 78,592 – Rs 48,000
= Rs 30,592 (Thirty thousand five hundred ninety two)
Thus, money will remain with merchant after purchase of radio = Rs 30,592 Answer
Question (8) A student multiplied 7236 by 65 instead of multiplying by 56. By how much was his answer greater than the correct answer? (Hint: Do you need to do both the multiplications?)
Solution
The result after incorrect multiplication = 7236 × 65
= 4,70,340 (Four lakh seventy thousand three hundred forty)
The result of multiplication by multiplying the number with correct number
= 7236 × 56
= 4,05,216 (Four lakh five thousand two hundred sixteen)
Thus difference in answer = result of incorrect multiplication – result of correct multiplication
= 4,70,340 – 4,05,216
= 65,124 (Sixty five thousand one hundred twenty four)
Thus, his answer was 65,124 greater than the correct answer Answer
Question (9) To stitch a shirt, 2 m 15 cm cloth is needed. Out of 40 m cloth, how many shirts can be stitched and how much cloth will remain? (Hint: convert data in cm.)
Solution
Given, cloth required to stitch one shirt = 2 m 15 cm
Total cloth available = 40 m
Thus, number of shirts can be stitched and after stitching length of remain cloth = ?
Cloth required to stitch one shirt = 2 m 15 cm
(To calculate we need to convert the cloth required in either meter or in centimetre)
We know that 1 meter = 100 cm
Therefore, 2 m = 2 × 100 cm = 200 cm
Thus, cloth required to stitch one shirt
= 200 cm + 15 cm = 215 cm
And cloth available = 40 m
= 40 × 100 cm = 4000 cm
Now total number shirts can be stitched using given cloth
= Total length of cloth available/Cloth required for 1 shirt
= 4000 cm/215 cm
= 18 1/130
Thus, total number of shirts can be made = 18, And cloth left = 130 cm
Now to know the cloth left in meter, we need to convert 130 cm into meter
Thus, 130 cm = 130/100 m
= 1.3 m
= 1 meter + 0.3 meter
Now, 0.3 meter = 0.3 × 100 cm = 30 cm
Thus, 0.3 meter = 30 cm
Thus, cloth left = 1 meter 30 cm
Thus, number of shirts can be stitched = 18 and cloth left 1 meter 30 cm Answer