An AP 5, 8, 11…has 40 Terms. Find the Last Term. Also Find the Sum of the Last 10 Terms | Bzziii.com

An AP 5, 8, 11…has 40 terms. Find the last term. Also find the sum of the last 10 terms.









First Term of the AP (a) = 5 

Common difference (d) = 8 - 5 = 3 

Last term 

= `"a"_40` = a + (40 - 1) d 

= 5 + 39 × 3 = 122 

Also `a_31` = a + 30d = 5 + 30 × 3 = 95 

Sum of last 10 terms = `"n"/2`(`"a"_31` + `"a"_40`) 

= `10/2` (95 + 122) 

= 5 × 217 = 1085







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