1). Use the given digits without repetition and make the greatest and the smallest five digit number.
a)6,2,4,8,5 c)4,9,3,1,7 e)3,0,9,8,6
b)7,0,1,2,6 d)1,6,7,2,5
Ans. a) 6,2,4,8,5
Greatest digit – 86542
Smallest digit – 24568
b) 7,0,1,2,6
Greatest digit – 76210
Smallest digit – 01267
c) 4,9,3,1,7
Greatest digit – 97431
Smallest digit – 13479
d) 1,6,7,2,5
Greatest digit – 76521
Smallest digit – 12567
e) 3,0,9,8,6
Greatest digit – 98630
Smallest digit – 03689
2). Arrange the following in ascending order as well as in descending order
a) 1897 , 3957 , 1788 , 2854 , 2653
b) 2631 , 1972 , 3491 , 993 , 1692
c) 7542 , 5700 , 1492 , 6349 , 4210
d) 8320 , 1271 , 5641 , 9372 , 4267
Ans. a) Ascending order:-1788 , 1897 , 2653 , 2854 , 3957
Descending order: – 3957 , 2854 , 2653 , 1897 , 1788
b) Ascending order: – 993 , 1692 , 1972 , 2631 , 3491
Descending order:-3491 , 2631 , 1972 , 1692 , 993
c) Ascending order:-1492 , 4210 , 5700 , 6349 , 7542
Descending order: – 7542 , 6349 , 5700 , 4210 , 1492
d) Ascending order:-1271 , 4267 , 5641 , 8300 , 9372
Descending order:-9371 , 8320 , 5641 , 4267 , 1271
3). Write the following in Roman numerals
a) 92 b) 49 c) 72 d) 36 e) 75 f) 84
Ans.
a) 92 = 90 + 2 b) 49 = 40 + 9
= (100 – 10) + 2 = (50 – 10) + 9
= XCII = XLIX
c) 72 = 70 +2 d) 36 = 30 + 6
= (50 + 20) +2 = (10 + 10 + 10) + 6
= LXXII = XXXVI
e)75 = 70 + 5 f) 84 = 80 + 4
= (50 + 20) + 5 = (50 + 30) + 4
= LXXV = LXXXIV
4). Write the following numbers in expanded form
a) 762 b) 483 c) 7432 d) 5654
Ans. a) 762 = 7 x 100 + 6 x 10 + 2 x 1
b) 483 = 4 x 100 + 8 x 10 + 3 x 1
c) 7432 =7 x 1000 + 4 x 100 + 3 x 10 + 2 x 1
d) 5654 = 5 x 1000 + 6 x 100 + 5 x 10 + 4 x 1
5). Insert commas suitably and write the name accordingly to Indian system of numeration:-
a) 5749030 b) 74920621 c) 83240209
Ans. a) 57,49,030 – Fifty seven lakh forty nine thousand thirty
b) 7,49,20,621 – Seven crore forty nine lakh twenty thousand six hundred twenty one
c) 8,32,40,209 – Eight crore thirty two lakh forty thousand two hundred nine.
6). Insert commas suitably and write the names according to International system of numeration:
a) 52461390 b) 64275138 c) 4702065
Ans. a) 52,461,390 – Fifty two million four hundred sixty one thousand three hundred ninety.
b) 64,275,138 – Sixty four million two hundred seventy five thousand one hundred thirty eight.
c) 4,702,065 – Four million seven hundred two thousand sixty five.
7). Estimate the following products:
a) 87 x 313 b) 958 x 387 c) 9 x 465 d) 698 x 485 e) 48 x 7
Ans. a) 87 x 313
Rounding off to tens
87 = 90 , 313 =310
Therefore, The product is = 90 x 310 = 27900
b) 958 x 387
Rounding off to hundred
958 = 1000 , 387 = 400
Therefore, The product is = 1000 x 400 = 400000
c) 9 x 465
Rounding off to tens
9 = 10 , 465 = 470
Therefore, The product is = 10 x 470 = 4700
d) 48 x 79
Rounding off to tens
48 = 50 , 79 = 80
Therefore, The product is = 50 x 80 = 4000
6). For a certain exhibition, the profit for the first week near Rs.8,700 , second week profit was Rs.13,200 , Rs.9,600 in the third week and Rs.6,500 in the fourth week. Calculate the total profit for all the four weeks
Ans. The profit in the 1st week = Rs.8,700
The profit in the 2nd week = Rs.13,200
The profit in the 3rd week = Rs.9,600
The profit in the 4th week = Rs. 6,500
Therefore the total profit for all the four weeks
=Rs 8,700 + Rs 13,200 + Rs 9600 + Rs 6500
=Rs 38,000
7). In a carton, there are 12 bottles of water. Each bottle containing 1L 500 ml of water. What will be the total litres of water in 25 cartons?
Ans. Quantity of water in 1 bottle = 1L 500 ml
= 1 x 1000 ml + 500 ml
= 1,500 ml
Total amount of water in 1 carton = 1500 ml x 12 bottles
= 18,000 ml
Total litres of water in 25 cartons = 18,000 x 25
= 4,50,000 ml
= 450L
8). In a jar, there is 2560 ml of juice. It has to be poured in 8 glasses. How much juice will be there in each glass.
Ans. Total juice in the jar = 2560 ml
No of glasses to be filled= 8
Amount of juice in each glass = 2560 ml ÷ 8
= 320 ml
Therefore, 320 ml of juice will be there in each glass.
9). The capacity of a water tank is 450 litres. Express its capacity in millilitres.
Ans. 1 litre = 1000 ml
Therefore, 450 litres = 450L x 1000 ml
= 4,50,000 ml
Therefore, The capacity of the water tank is 4 lakh 50 thousand millilitres.