Question

Q. The number of numbers of the form 30a0b03 that are
divisible by 13, where a, b are digits, is
(A) 5
(B) 6
(C) 7
(D) 0​

Answer 1

Answer:

6

Step-by-step explanation:

let a=6,b=6

PUT THE VALUES

3060603÷13=235431

Answer 2

6 and the number is 3060603 which is divisible by 13.

Explanation:

In order to determine the correct number of form 3060603, let us first understood which numbers are actually divisible by 13. The simple rule is known as divisibility rule.

Specifically, for determining the divisibility with 13, follow these steps:

The number is: 3060603

$306060+3 \times 4=306060+12=306072$

Hence, pick all digits except last digit and add the result of multiplication of last digit with 4 to the said digits. Then, follow same step with the resultant figure.

$\begin{array}{l}{30607+2 \times 4=30607+8=30615} \\ \\{3061+5 \times 4=3061+20=3081} \\ \\{308+1 \times 4=308+4=312} \\ \\{31+2 \times 4=31+8=39}\end{array}$

Now, the final result is 39 which is divisible by 13. This means that the original number i.e. 3060603 is divisible by 13.