Question

If 215y2 is a multiple of 3 and 11, where y is a single digit number, then find the value of y.​

Answer 1

Step-by-step explanation:

1

2+1+y+5=8+y

y=9-8

y is 1

Answer 2

Value of y is 8 if 215y2 is a multiple of 3 and 11, where y is a single digit number

Given:

• 215y2 is a multiple of 3 and 11
• y is a single digit

To Find:

• Value of y

Solution:

• A number is Divisible by 3 if sum of digit is divisible by 3
• A number is divisible by 11 if difference between sum of digits at odd and even places is divisible by 11

Step 1:

Find sum of Digits in 215y2

2 + 1 + 5 + y + 2

=10 + y

10 + y is divisible by 3  if

y = 2 , 5 , 8

Step 2:

Find difference between sum of digits at odd and even places in 215y2

(2 + 5 + 2) -(1 + y)

= 8 - y  

8 - y is divisible by 11 if y = 8  

Common solution from both is 8

Value of y is 8