Punjab State Board PSEB 5th Class Maths Book Solutions Chapter 1 Numbers Ex 1.4 Textbook Exercise Questions and Answers.
PSEB Solutions for Class 5 Maths Chapter 1 Numbers Ex 1.4
Question 1.
Round off the following numbers to the nearest tens.
(a) 270
(b) 809
(c) 6465
(d) 9782
(e) 908
(f) 100
(g) 25338
(h) 1756.
Solution:
(a) In the number 270, ones digit is 0, which is less than 5, so, tens digit remains the same.
∴ Required number = 270.
(b) In the number 809, ones digit is 9, which is greater than 5, so, tens digit is increased by 1 and units digit is replaced by 0.
∴ Required number = 810.
(c) In the number 6465, ones digit is 5, which is equal to 5, so, tens digit is increased by 1 and ones digit is replaced by 0.
∴ Required number = 6470.
(d) In the number 9782, ones digit is 2, which is less than 5, so, tens digit remains the same and ones digit is replaced by 0.
∴ Required number = 9780.
(e) In the number 908, ones digit is 8, which is greater than 5, so, tens digit is increased by 1 and units digit is replaced by 0.
∴ Required number = 910.
(f) In the number 100, ones digit is 0, which is less than 5, so, tens digit remains the same.
∴ Required number = 100.
(g) In the number 25338, ones digit is 8, which is greater than 5, so, tens digit is increased by 1 and ones digit is replaced by 0.
∴ Required number = 25340.
(h) In the number 1756, ones digit is 6, which is greater than 5, so, the tens digit is increased by 1 and units digit is replaced by 0.
∴ Required number = 1760.
Question 2.
Round off the following numbers to the nearest hundreds.
(a) 325
(b) 875
(c) 990
(d) 4580
(e) 568
(f) 63535
(g) 85972
(h) 75069.
Solution:
(a) In the number 325, tens digit is 2, which is less than 5, so, hundreds digit remains the same and 25 is replaced by 00.
∴ Required number = 300.
(b) In the number 875, tens digit is 7, which is greater than 5, so, hundreds digit is increased by 1 and 75 is replaced by 00.
∴ Required number = 900.
(c) In the number 990, tens digit is 9, which is greater than 5, so, hundreds digit is increased by 1 and 90 is replaced by 00.
∴ Required number = 1000.
(d) In the number 4580, tens digit is 8, which is greater than 5, so, hundreds digit is increased by 1 and 80 is replaced by 00.
∴ Required number = 4600.
(e) In the number 568, tens digit is 6, which is greater than 5, so, hundreds digit is increased by 1 and 68 is replaced by 00.
∴ Required number = 600.
(f) In the number 63535, tens digit is 3, which is less than 5, so, hundreds digit remains the same and 35 is replaced by 00.
∴ Required number = 63500.
(g) In the number 85972, tens digit is 7, which is greater than 5, so, hundreds digit is increased by 1 and 72 is replaced by 00.
∴ Required number = 86000.
(h) In the number 75069, tens digit is 6, which is greater than 5, so, hundreds digit is increased by 1 and 69 is replaced by 00.
∴ Required number = 75100.
Question 3.
Round off the following numbers to the nearest thousands.
(a) 7890
(b) 8901
(c) 45982
(d) 5650
(e) 63520
(f) 50460
(g) 60008
(h) 9999
Solution:
(a) In the number 7890, the hundreds digit is 8, which is greater than 5, so, thousands digit is increased by 1 and 890 is replaced by 000.
∴ The required number = 8000.
(b) In the number 8901, the hundreds digit is 9, which is greater than 5, so, thousands digit is increased by 1 and 901 is replaced by 000.
∴ The required number = 9000.
(c) In the number 45982, the hundreds digit is 9, which is greater than 5, so, thousands digit is increased by 1 and 982 is replaced by 000.
∴ The required number = 46000.
(d) In the number 5650, the .hundreds digit is 6, which is greater than 5, so, thousands digit is increased by 1 and 650 is replaced by 000.
∴ The required number = 6000.
(e) In the number 63520, the hundreds digit is 5, so, thousands digit is increased by 1 and 520 is replaced by 000.
∴ Required number = 64000. .
(f) In the number 50460, the hundreds digit is 4, which is less than 5, so, thousands digit remains the same and 460 is replaced by 000.
∴ Required number = 50000.
(g) In the number 60008, the hundreds digit is 0, which is less than 5, so, thousands digit remains the same and 008 is replaced by 000.
∴ Required number = 60000.
(h) In the number 9999, hundreds digit is 9, which is greater than 5, so, thousands digit is increased by 1 and 999 is replaced by 000.
∴ The required number = 10000.
Question 4.
Round off the following number to the nearest ten thousands.
(a) 27900
(b) 80901
(c) 46580
(d) 12550
(e) 99998
(f) 10001
(g) 23235
(h) 23568.
Solution:
(a) In the number 27900, the thousands digit is 7, which is greater than 5, so, ten thousands digit is increased by 1 and 7900 is replaced by 0000.
∴ The required number = 30000.
(b) In the number 80901, the thousands digit is 0, which is less than 5, so, ten thousands digit remains the same and 0901 is replaced by 0000.
∴ The required number = 80000.
(c) In the number 46580, the thousands digit is 6, which is greater than 5, so, ten thousands digit is increased by 1 and 6580 is replaced by 0000.
∴ The required number = 50000.
(d) In the number 12550, the thousands digit is 2, which is less than 5, so, ten thousands digit remains the same and 2550 is replaced by 0000.
∴ The required number = 10000.
(e) In the number 99998, the thousands digit is 9, which is greater than 5, ten thousands is increased by 1 and 9998 is replaced by 0000.
∴ The required number = 100000.
(f) In the number 10001, thousands digit is 0, which is less than 5, so, ten thousands digit remains the same and 0001 is replaced by 0000.
∴ The required number = 10000.
(g) In the number 23235, the thousands digit is 3, which is less than 5, so, ten thousands digit remains the same and 3235 is replaced by 0000.
∴ The required number = 20000.
(h) In the number 23568, the thousands digit is 3, which is less than 5, so, ten thousands digit remains the same and 3568 is replaced by 0000.
∴ The required number = 20000.
Question 5.
Round off the following numbers to the nearest tens, nearest hundreds and nearest thousands :
(a) 1625
(b) 1982
(c) 25200
(d) 21218
(e) 35462
(f) 39126
(g) 65915
(h) 99199.
Solution:
(a) 1625 rounded off to the nearest tens = 1630, 1625 rounded off to the nearest hundred = 1600, 1625 rounded off to the nearest thousands = 2000.
(b) 1982 rounded off to the nearest tens = 1980, 1982 rounded off to the nearest hundred = 2000, 1982 rounded off to the nearest thousands = 2000.
(c) 25200 rounded off to the nearest tens = 25200, 25200 rounded off to the nearest hundred = 25200, 25200 rounded off to the nearest thousands = 25000
(d) 21218 rounded off to the nearest tens = 21220, 21218 rounded off to the nearest hundred = 21200, 21218 rounded off to the nearest thousands = 21000.
(e) 35462 rounded off to the nearest tens = 35460, 35462 rounded off to the nearest hundred = 35500, 35462 rounded off to the nearest thousands = 35000
(f) 39126 rounded off to the nearest tens = 39130, 39126 rounded off to the nearest hundred = 39100, 39126 rounded off to the nearest thousands = 39000
(g) 65915 rounded off to the nearest tens = 65920, 65915 rounded off to the nearest hundreds = 65900, 65915 rounded off to the nearest thousands = 66000
(h) 99199 rounded off to the nearest tens = 99200, 99199 rounded off to the nearest hundreds = 99200, 99199 rounded off to the nearest thousands = 99000
Question 6.
Write the smallest and greatest number that can be rounded off to the nearest thousand, to get 5000 ?
Solution:
The smallest number that can be rounded off to the nearest thousands to get 5000 = 4500 The greatest number which can be rounded off to the nearest thousands, to get 5000 = 5499.
Question 7.
If the rounding off of 341 to the nearest tens is 340 write all the numbers which while rounding off to the nearest tens give the figure of 340?
Solution:
All the numbers which while rounding off to the nearest tens give the figure of 340 = 335, 336, 337, 338, 339, 340, 341, 342, 343, 344.