Si [tex] \ frac{a}{3} = \ frac{b}{7} = \ frac{c}{4} [ / tex] ; a + b + c = 84Hallar : b + c?
Si [tex] \ frac{a}{3} = \ frac{b}{7} = \ frac{c}{4} [ / tex] ; a + b + c = 84 Hallar : b + c.
Si [tex] \ frac{a}{3} = \ frac{b}{7} = \ frac{c}{4} [ / tex] ; a + b + c = 84 Hallar : b + c.
A / 3 = b / 7 :
7a = 3b : b = 7a / 3
a / 3 = c / 4 : c = 4a / 3
a + b + c = 84
Reemplazo b y c por sus valores de a
a + (7a / 3) + (4a / 3) = 84
3a / 3 + 7a / 3 + 4a / 3 = 84
(3a + 7a + 4a) / 3 = 84
14a / 3 = 84
14a = 3(84)
14a = 252
a = 18
Ahora hallo b y c
b = 7a / 3
b = 7(18) / 3 = 42
c = 4a / 3 = 4(18) / 3
c = 24
a = 18 ; b = 42 ; c = 24
b + c = 42 + 24 = 66
b + c = 66.
Es primero multiplicas luego divides y luego sumas.
1) 2 (c / 7) = 3 / 42c = 3 × 7 / 4c = (21 / 4) / 2c = 21 / 82) (g + 3) / 4 + 4g / 5 = 55g + 15 + 16g = 10021g = 85g = 85 / 213) (e - 5) / 9 = (e - 25) / 55e - 25 = 9e - 225200 = 4e50 = e.