There are five terms in the a.p the sum of these terms is 55and the fo...
Let the 5 terms be (a - 2d), (a - d), a , (a + d), (a + 2d)
Sum of all terms = 5a = 55
⇒ a = 11
4ᵗʰ term = 5 + (1ˢᵗ term + 2ⁿᵈ term)
⇒ a + d = 5 + a - 2d + a - d
⇒ 4d = 5 + a
⇒ d = 16/4 = 4
On substituting the values of a and d we get the terms as 3, 7, 11, 15, 19
There are five terms in the a.p the sum of these terms is 55and the fo...
Given information:
- There are five terms in the arithmetic progression (a.p).
- The sum of these terms is 55.
- The fourth term is five more than the sum of first two terms.
To find:
- The terms of the arithmetic progression.
Solution:
Let us assume that the first term of the arithmetic progression is 'a' and the common difference is 'd'. Then, we can write the terms of the a.p as:
a, a+d, a+2d, a+3d, a+4d
Using the given information, we can form two equations:
- Sum of the terms = 55
a + (a+d) + (a+2d) + (a+3d) + (a+4d) = 55
5a + 10d = 55
a + 2d = 11 ---- equation (1)
- Fourth term = sum of first two terms + 5
a+3d = (a + a+d) + 5
a+3d = 2a + d + 5
a + 2d = 5 ---- equation (2)
Solving equations (1) and (2), we get:
a = 2
d = 3
Therefore, the terms of the arithmetic progression are:
2, 5, 8, 11, 14
Verification:
- Sum of the terms = 2+5+8+11+14 = 40
- Fourth term = 11 = Sum of first two terms (2+5) + 5.
To make sure you are not studying endlessly, EduRev has designed Class 10 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 10.