the first term of an ap is 19 . the ratio of the 6th term to 22nd term is 11:31. find the ap
Answers
Answer:
Given: 6th term A6= 20, 11th term A11=30
we have, An= A1+(n-1)d
=> A6=A1+(6–1)d
=> 20=A1+5d ——equation (1)
A11=A1+(11–1)d
=> 30=A1+(11–1)d
=> 30= A1+10d ——equation (2)
equating 1 and 2, we have
=> d=2, substitute in eq(1)
=> 20= A1+5(2)
=>A1=20–10=10
Hence, the first term A1=10 and common difference d=2.
Step-by-step explanation:
Answer:
The first term A1 = 10 and common difference d = 2.
Step-by-step explanation:
Given,
6th term A6 = 20
11th term A11 = 30
We have, An = A1 + (n - 1) d
=> A6 = A1 + (6 - 1) d
=> 20 = A1 + 5d (equation 1)
A11 = A1 + (11 - 1) d
=> 30 = A1 + (11 - 1) d
=> 30 = A1 + 10d (equation 2)
Equation 1 & 2, we have
=> d = 2, substituting in (equation 1)
=> 20 = A1 + 5 (equation 2)
=> A1 = 20 - 10 = 10
Hence, the first term A1 = 10 and common difference d = 2.