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Find the 20th term from the last term of the AP: 3, 8, 13, …. 253.
By BYJU'S Exam Prep
Updated on: September 25th, 2023
The 20th term from the last term of the AP: 3, 8, 13, …. 253 is 158. A series of numbers is called an “arithmetic progression” (AP) when there is a consistent difference between any two subsequent numbers. Now we have to evaluate the required term from the given Arithmetic Progression
Given, AP – 3, 8, 13, …. 253
We shall reorder the AP because we need to analyse the 20th term from the previous one., i.e. 253, 248, ….., 13, 8, 3
In the given series first term a = 253
and, common difference d = 248 – 253 = -5
We know that the nth term of an AP is defined by an = a + (n – 1)d
So, to evaluate the 20th term we will calculate a20
a20 = 253 + (20 – 1) (-5)
a20 = 253 – 95
a20 = 158
A succession of terms with a common difference between them that has a constant value is known as an arithmetic progression. It is employed to generalise a collection of trends that we notice in daily life. As an illustration, AP is used to forecast any sequence, such as when a person is waiting for a cab. He or she can anticipate when the next taxi will arrive assuming that traffic is moving at a steady speed.
Summary:
Find the 20th term from the last term of the AP: 3, 8, 13, …. 253.
The 20th term from the last term of the AP: 3, 8, 13, …. 253 is 158. When any two succeeding numbers in a series diverge consistently from one another, the sequence of numbers is referred to as a “arithmetic progression” (AP).
