Find a30 – a20 for the A.P. -9, -14, -19, -24.

1.	Find a30 – a20 for the A.P. -9, -14, -19, -24.
Answer» We know that a_n = a + (n – 1)d So, a₃₀ – a₂₀ = (a + 29d) – (a + 19) =10d Given A.P. -9, -14, -19, -24 Here, a = -9 and d = -14 – (-9) = = -14 + 9 = -5 So, a₃₀ – a₂₀ = 10d = 10(-5) = -50

Answer»

We know that a_n = a + (n – 1)d

So, a₃₀ – a₂₀ = (a + 29d) – (a + 19) =10d

Given A.P. -9, -14, -19, -24

Here, a = -9 and d = -14 – (-9) = = -14 + 9 = -5

So, a₃₀ – a₂₀ = 10d

= 10(-5)

= -50

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