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Ex 5.3, 13 - Chapter 5 Class 10 Arithmetic Progressions (Term 2)
Last updated at March 22, 2021 by Teachoo
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Ex 5.3
Ex 5.3, 1 (i)
Ex 5.3, 1 (ii)
Ex 5.3, 1 (iii) Important
Ex 5.3, 1 (iv)
Ex 5.3, 2 (i)
Ex 5.3, 2 (ii)
Ex 5.3, 2 (iii) Important
Ex 5.3, 3 (i)
Ex 5.3, 3 (ii)
Ex 5.3, 3 (iii)
Ex 5.3, 3 (iv) Important
Ex 5.3, 3 (v)
Ex 5.3, 3 (vi) Important
Ex 5.3, 3 (vii)
Ex 5.3, 3 (viii) Important
Ex 5.3, 3 (ix)
Ex 5.3, 3 (x)
Ex 5.3, 4
Ex 5.3, 5
Ex 5.3, 6 Important
Ex 5.3, 7
Ex 5.3, 8
Ex 5.3, 9
Ex 5.3, 10 (i)
Ex 5.3, 10 (ii) Important
Ex 5.3, 11 Important
Ex 5.3, 12
Ex 5.3, 13 You are here
Ex 5.3, 14 Important
Ex 5.3, 15
Ex 5.3, 16 Important
Ex 5.3, 17
Ex 5.3, 18 Important
Ex 5.3, 19 Important
Ex 5.3, 20 Important
Chapter 5 Class 10 Arithmetic Progressions
Serial order wise
Transcript
Ex 5.3, 13 Find the sum of first 15 multiples of 8. Multiples of 8 are 8, 16, 24,β¦ Since difference is same, it is an AP We need to find sum of first 15 multiples We use formula Sn = π/2 (2π+(πβ1)π) Here, n = 15, a = 8 & d = 16 β 8 = 8 Putting values in formula Sn = π/π (ππ+(πβπ)π ) = 15/2(2 Γ 8+(15β1) Γ 8) = 15/2 (16+14 Γ 8) = 15/2 (16+112) = 15/2 Γ 128 = 960 Therefore, the sum of first 15 multiples of 8 is 960
