Class 10 Maths Chapter 5
10th Maths Arithmetic Progression Important Questions
Important Questions of Class 10 Maths
The common difference of two different arithmetic progressions are equal.The first term of the first progression is 3 more than the first term ofsecond progression. If the 7 th term of first progression is 28 and 8 th term of second progression is 29, then find the both different arithmetic progressions
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A+6d=28
=a+3+6d=28
a+6d=24–––––––1
a+7d=2a–––––––2
Solving 1 and 2
d=4and a=1
So the first ap : 4,8,12…………
And second ap:1, 5,9…..
A +6d= 28
A+3+6d = 28
A + 6d = 25…….1
A+ 7d = 29………2
Add 1 and 2
A = 1 D = 4
1st AP = 4,8,12,16……
2nd AP = 1,5,9,13
Let the first term of second AP = a
So, the first term of first AP = a + 3
7th term of first progression is 28
So, A + 6D = 28
⇒ a + 3 + 6D = 28
⇒ a + 6D = 25 … (1)
8th term of the second progression is 29
⇒ a + 7D = 29 … (2)
Solving (1) and (2), we have
D = 4 and a = 1
So, the first AP: 4, 8, 12 …
And the second AP: 1, 5, 9…