How to solve the following:

4a/15 = 3/5

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We need to solve the equation "4a/15 = 3/5"

This equation can be rewritten as:

a*(4/15) = 3/5

To make the left hand side of the equation equal to a we multiply bot side of equation by 15/4. Giving

a*(4/15)*(15/4) = (3/5)*(15/4)

We simplify this equation in following steps.

a*(4*15)/(15*4) = (3*15)/5*4)

a*(60/60) = 45/20

a = 9/4 = 2.25

To solve 4a/15 = 3/5.

Solution:

4a/15 =3/5. Multiply by 15 both sides :

15*4a/15= 3*15/5 Or

4a = 9. Divide by 4 both sides:

a = 9/4 = 2.25

given that,

4a/15=3/5

we may written as

4a=3*15/5

or,4a=3*3

or,4a=9

or,a=9/4

a=2.25

To solve this question, the most important part is to know that 'a' is what you have to find.

In this quetion, it is easy to see what 'a' is because 15 is a multiple of 5. If you mutiply 5 by 3, you will get 15! This is what the two denominators are. So, you have to do the same thing to the numeratorl you have to multiply 3. 3x3 is 9, and that is equal to 4a.

To put it neatly, it is:

4a/15=3/5

4a/15=9/15 (At this stage, you don't have to be concerned of the denominators because they are equal)

4a=9

a=9/4

a=2+1/4

This can be said because with the demonimators equal, the numerators have to be equal as well.

So, in doing these sorts of questions, you have to make the denominators of both sides equal, and then solve the variable.

This is how I would do it

4a/15=3/5

5(4a)=15(3)

20a=45

a=2.25 or a= 2 1/4

4a/15 = 3/5

4a = (3/5) x 15 = 9

a = 9/4

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