Question

Calcule o valor de X ou Y nas proporções a seguir:

a)x-------16
6-------12


b)7-------5
5-------y

c) 3x------2
4------6

d) 4-----20
5------x+1

Answer 1

?multiplicando em Cruz...

a) 12x = 6*16 x = 96/12 x= 8

b) 7y = 5*5 y= 25/7

c) 3x*6 = 2*4 12x = 8 x= 12/8 = 3/2

d) 4x+4 = 100 4x = 100-4 x = 96/4 x= 24

Answer 2

a)

$x\rightarrow16 \\ 6\rightarrow12 \\ 12x = 96 \\ x = \dfrac{96}{12} \\\boxed{\boxed{\mathsf{x = 8}}}$

b)

$7\rightarrow5 \\ 5\rightarrow \:x \\ 7x = 25 \\\boxed{\boxed{\mathsf{x = \dfrac{25}{7} }}}$

c)

$3x\rightarrow2 \\ 4\rightarrow \:6 \\ 18x = 8 \\\boxed{\boxed{\mathsf{x = \dfrac{8 \div 2}{18 \div 2} = \dfrac{4}{9}}}}$

d)

$4\rightarrow \: 20\\ 5\rightarrow \:x + 1 \\ 4x + 4 = 100 \\ 4x = 100 - 4 \\ 4x = 96$

$\boxed{\boxed{\mathsf{x = \dfrac{96}{4} = 24 }}}$