a20 - a12 = -32
Arithmatic progression question
Answers
Answered by
12
Arithmetic Progression
→ 20th term = a + 19d
→ 12th term = a + 11d
→ (a + 19d) - (a + 11d) = - 32
→ a + 19d - a - 11d = - 32
→ 8d = - 32
→ d = - 4
Verification
→ a + 19(- 4) - a - 11(- 4) = 32
→ a - 76 - a + 44 = 32
→ - 32 = - 32
→ L.H.S = R.H.S
Hence value of common difference is - 4.
Answered by
14
Answer: d = -4
Step by step explanation:
Given that:
- a20 - a12 = -32
We know that,
a20 = a + (20 - 1) d
a20 = a + 19d.. (1)
Similarly,
a12 = a + 11d.. (2)
From eq. (1) and (2),
(a + 19d) - (a + 11d) = -32
8d = -32
Dividing both sides by 8,
- d = -4
Thus, Value of d is -4.
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