find the sum of first 20 terms of the arithmetic progression 3, 8, 13​

2 thoughts on “find the sum of first 20 terms of the arithmetic progression 3, 8, 13​”

1. Step-by-step explanation:

   common difference (d)=5

   first term(t n)=3

   n=20

   [tex]tn = a + (n – 1)d[/tex]

   [tex]t20 = 3 + (20 – 1)5 = 3 + 19 \times 5[/tex]

   [tex]t20 = 98[/tex]

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2. ☆ ΛПƧЩΣЯ ☆

   [tex]given \\ a = 3 \: \: d = 5 \: \:n = 20 \\ s20 = \frac{n}{2} (2a + (n – 1)d) \\ = \frac{20}{2} (2(3) + (20 – 1)5) \\ = 10(6 + 19 \times 5) \\ [/tex]

   [tex] = 10 \times 101 \\ = 1010[/tex]

   ✈ 5 thanks ✈️

   ➡️ Fo I l o w me ⬅️

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