Question

How many numbers of two digits are divisible by 7?

Chapter - Arithmetic Progression

Class 10

Explaination Is Must ;)

Answer 1

Answer:

13

Step-by-step explanation:

Numbers divisible by 7 are

7,14,21,28...

∴ Lowest two digit number divisible by 7 : 14.

∴ Highest two digit number divisible by 7 : 98

So, the series start with 14 and ends with 98.

Difference between numbers is 7.

So, the AP will be 14,21,28..98.

Last term of the series is 98.

First term a = 14.

Common difference d = 7.

Last term = an = 98.

Value of n:

a(n) = a + (n - 1) * d

98 = 14 + (n - 1) * 7

98 - 14 = (n - 1) * 7

84 = 7n - 7

91 = 7n

n = 13.

Therefore, there are 13 two-digit numbers divisible by 7.

Hope it helps!

Answer 2

Heyy mate ❤✌✌❤

Here's your Answer....

⤵️⤵️⤵️⤵️⤵️⤵️⤵️

AP: 14 , 21 , 28 , 35, ............... , 98.

a = 14

d = 7

an= 98.

Therefore,

an = a + (n-1) ×d

98 = 14+ (n-1) × 7

98 - 14 =( n - 1) × 7

84/ 7 = n - 1

12 = n- 1

n = 13.
✔✔✔

Therefore, only 13 two digit numbers are divisible by 7.