CBSE Class 8 Mathematics Playing with Numbers Notes

Question. If a number N + 5 leaves a remainder of 1. What are the possible ones digit of N.
Answer : 1 and 6

Question. What is the difference between two digit largest and smallest number which is divisible by 2.
Answer : 88

Question. Which number is divisible by both 5 and 10.
98175, 13260, 12345, 5675, 74384
Answer : 13260

Question. If 312x is a multiple of 5. Where x is a digit. What is the least value of x.
Answer : 0

Question. Find two digit number ab in general form
Answer : 10a + b

Question. If the difference of a two digit number (ab) where a > band number obtained by reverse the digit is divided by 9. What is the remainder?
Answer : 0

Question. Find the smallest four digit number which is divisible by 3.
Answer : 1002

Question. If the division N + 2 leaves a remainder of 1. What might be the highest ones digit of N.
Answer : 9

Question. If 21433k is a multiple of 9 where k is a digit. What is the value of k.
Answer : 5

Question. If the division 1234x 3 leaves a remainder of 1. What might be the least value of x.
Answer : 0

Question. Which number is divisible by 10.
82513, 42165, 12540, 34255, 16751
Answer : 12540

Question. 21y5 is a multiple of 3. Where y is a digit. What is the least value of y.
Answer : 1

Question. If 98m341 is a multiple of 3, where m is a digit. What is the least value of m.
Answer : 2

Question. If 39P625 is a multiple of 11. Where P is a digit. What is the value of P.
Answer : 4

Question. If 376x5 is a multiple of 3, where x is a digit. What is the highest value of x.
Answer : 9

Question. What least number should be subtract from 15287 so that the number is divisible by 3.
Answer : 2

Question. Which number is divisible by 3.
10301, 24680, 12345, 35243, 34567
Answer : 12345

Question. What is the difference between the smallest three digit number and largest two digit number, divisible by 3.
Answer : 3

Question. Which number is divisible by both 2 and 11
1749, 2760, 8118, 2462
Answer : 8118

Question. Which number is divisible by both 2 and 3.
12345, 24680, 20304, 8007, 8642
Answer : 9875

Question. Which number is divisible by 5
20304, 8009, 15432, 9875, 26257
Answer : 9875