Question

How many 2-digit numbers can be formed from the digits 8, 1, 3, 5 and 4 assuming
(a) repetition of digits is allowed?
(b) repetition of digits is not allowed?​

Answer 1

Answer:

• 81 83 85 84 18 13 15 14 38 31 35 34 58 51 53 54 48 41 43 45
• 20 numbers can be formed by repetition of the numbers

Step-by-step explanation:

• 18 35 4
• only 2 numbers can be formed by not repeating the numbers

• I think I have gone wrong on the not repeating one so please sorry for that