182k views
4 votes
1.2/4=x/28 what is the value of x

2 Answers

4 votes

Answer:

8.4

Explanation:


(1.2)/(4) =
(x)/(28)

cross multiply to solve for x:

(1.2)(28) = 4x

4x = 33.6

x = 33.6/4 = 8.4

User Mining
by
7.2k points
5 votes

Answer:

8.4

Explanation:

You want to know the value of x that satisfies 1.2/4 = x/28.

One-step equation

The equation ...

x/28 = 1.2/4

can be solved in one step by multiplying by 28.

x = 28(1.2/4) = 8.4

The value of x is 8.4.

__

Additional comment

The fraction involving x can be cleared by multiplying by its denominator, effectively the inverse of the coefficient of x. This is the same way you solve any similar one-step equation.

Often, you are told to "cross-multiply" a proportion. Doing that gives you ...

4·x = 28·1.2

Then you have to divide by 4 (multiply by the inverse of the coefficient of x) to find the value of x:

x = 28·1.2/4 . . . . same as above.

That is, there is no need to multiply by 4, and then divide by 4. You can simply multiply by 28 and be done.

User Haris Ali
by
8.2k points