List the proportions and find that the ratio of 0.25 to 8 / 1 is equal to the ratio of X to 10 4 / 1 of number a is equal to 5 / 1 of number B. find the ratio of number a to number B Zhang Bin on the computer to scale up the following photos, enlarged the photo is 13.5 cm long, how many cm wide? 4 cm high, 6 cm long. It is a rectangle

List the proportions and find that the ratio of 0.25 to 8 / 1 is equal to the ratio of X to 10 4 / 1 of number a is equal to 5 / 1 of number B. find the ratio of number a to number B Zhang Bin on the computer to scale up the following photos, enlarged the photo is 13.5 cm long, how many cm wide? 4 cm high, 6 cm long. It is a rectangle

1. 1/8*x=10*0.25 x=20
2. 1 / 4 a = 1 / 5 B A / b = 4 / 5
3. x/13.5=4/6 x=9
I hope my answer will help you

(a + 10) / x = y, X is not equal to 0, when a is fixed, is x proportional to y? If so, what is the proportion?

Proportional, inverse!
In Mathematics: the product of multiplication of two arbitrary numbers is a constant
Hope the answer can help you, where is not clear to ask

The ratio of X to 2 / 9 is equal to the ratio of 9 / 10 to 3 / 4

x/(2/9)=(9/10)/(3/4)
(3/4)X=1/5
X=4/15