Question

calcule o valor de "?", sabendo que as frações sao equivalentes:
a) 2/3 = 18/?

b)7/8 = ?/40

c)21/? = 7/4

Answer 1

calcule o valor de "?", sabendo que as frações sao equivalentes:
a) 2/3 = 18/?

b)7/8 = ?/40

c)21/? = 7/4

A)

$\dfrac{2}{3} =\dfrac{18}{?} \\ 2? = 3 * 18 \\ 2? = 54 \\ ? =\dfrac{54}{2} \\ ? = 27$

B)

$\dfrac{7}{8} =\dfrac{?}{40} \\ 8? = 7 * 40 \\ 8? = 280 \\ ? =\dfrac{280}{7} \\ ? = 40$

C)

$\dfrac{21}{?} =\dfrac{7}{4} \\ 7? = 4*21 \\ 7? = 84 \\ ? =\dfrac{84}{7} \\ ? = 12$