Question

Quantos múltiplos de 5 existem de - 170 a 280 ?

Answer 1

-170, -165, -160, -155, -150, -145, -140, -135, -130, -125, -120, -115, -110, -105, -100, -95, -90, -85, -80, -75, -70, -65, -60, -55, -50, -45, -40, -35, -30, -25, -20, -15, -10, -5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, 250, 255, 260, 265, 270, 275, 280

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a1 = -170
r = 5
n = ?
an = 280

280 = a1 + (n - 1)r
280 = -170 + (n - 1)5
280 = -170 + 5n - 5
280 = -175 + 5n
-5n = -175 - 280
5n = 455
n = 455/5
n = 91 <<<<<<<<<<<<<<<<<<<<