Question

ayúdenme a resolver estos problemas pls

a) 1/8n = 5/2

b) 3/2a = 21/4

c) 3/8 = x1/5

d) 9/10 = 9/100

f) 5/7 = 10/14x

g) 3/7 = 4/9a

f) 2/5 = 4/30b

Answer 1

a)

$1 \div 8 \times n = 5 \div 2 \\ \frac{1}{8} n = 2.5 \\ n = 20$

b)

$3 \div 2 \times a = 21 \div 4 \\ \frac{3}{2} a = 5.25 \\ a = \frac{2}{3} \times 5.25 \\ a = \frac{2}{3} \times \frac{21}{4} \\ a = \frac{7}{2}$

c)

$3 \div 8 = x1 \div 5 \\ 15 = 8x \\ 8x = 15 \\ x = \frac{15}{8}$

d) Falso.

$9 \div 10 = 9 \div 100 \\ 0.9 = 0.09$

f)

$5 \div 7 = 10 \div 14 \times x \\ \frac{5}{7} = \frac{5}{7} x \\ 1 = x \\ x = 1$

g)

$3 \div 7 = 4 \div 9 \times a \\ \frac{3}{7} = \frac{4}{9} a \\ \frac{27}{28} = a \\ a = \frac{27}{28}$

f)

$2 \div 5 = 4 \div 30 \times b \\ 0.4 = \frac{4}{30} b \\ 0.4 = \frac{2}{15} b \\ \frac{15}{2} \times 0.4 = b \\ \frac{15}{2} \times \frac{2}{5} = b \\ 3 = b \\ b = 3$

(me parece que te equivocaste en las letras para enumerar los ejercicios. Ej: a, b, c, d)