Question

Question 10 If 17 th term of an A.P. exceeds its 10 th term by 7. Find the common difference.

Class 10 - Math - Arithmetic Progressions Page 106

Answer 1

given that
a+16d-(a+9d)=7
a+16d-a-9d =7
7d=7
d=7/7=1
therefore common difference=1

Answer 2

AP  ( Arithmetic progression). A list of numbers a1, a2, a3  ………….. an is called an arithmetic progression.

General term or nth term of A.P

The general term or nth term of A.P is given by an = a + (n – 1)d,

where a is the first term, d is the common difference and n is the number of term.

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Solution:

We know that,

For an A.P., an = a + (n − 1) d

a17 = a + (17 − 1) d
a17 = a + 16d

Similarly, a10 = a + 9d

It is given that

a17 − a10 = 7

(a + 16d) − (a + 9d) = 7

a- a +16d -9d =7

7d = 7

d = 1

Hence the common difference is 1.

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hope this will help you......