Question

HELP!
calcule a soma dos múltiplos de 4 compreendidos entre 13 e 462.

Answer 1

Entre 13 e 462 (r = 4) → De 16 a 460

$A_{n} = a_{1} + (n -1) . r$
460 -16 = (n -1) . 4
444/4 = n -1
111 + 1 = n
112 = n

$S_{n} = \frac{ ( a_{1} + a_{n} ) . n}{2}$
s112 = (16 + 460) . 112/2
s112 = 476 . 56
s112 = 26656