Question

Solve the application problem.

In one day a baker used 1/3
of a pound of flour, then 1/4
of a pound of flour, then 5/12
of a pound of flour. How much flour was used that day?

Answer 1

1 cup

Explanation:

What is a fraction?

A fraction is a fragment of a whole number, used to define parts of a whole. The whole can be a whole object, or many different objects. The number at the top of the line is called the numerator, whereas the bottom is called the denominator.

To solve for the total number of cups used, we need to first convert each fraction to have a common denominator.

What is a common denominator?

A common denominator consists of two or more fractions that have the same denominator. This makes it easier to perform numeric equations, and to solve them.

As of now, each fraction looks like this:

• 
  `(1)/(3) +(1)/(4) +(5)/(12)`

Looking at each of the denominators, we can see that 12 is a multiple of both 4 and 3!

So, let's convert
`(1)/(3)`.

• 3 can be multiplied by 4 to get 12.

Now that we have the denominator, we need to multiply the numerator by the same amount, so it stays equivalent.

• 1 can be multiplied by 4 to get 4.

• 
  `(1)/(3) =(4)/(12)`

Now let's convert
`(1)/(4)`.

4 can be multiplied by 3 to get 12.

1 can be multiplied by 3 to get 3.

• 
  `(1)/(4) =(3)/(12)`

Now, each fraction looks like this:

• 
  `(4)/(12)+ (3)/(12)+ (5)/(12)`

Adding up the numerators:

• 4 + 3 + 5 = 12

Adding that back on top of the denominator:

• 
  `(12)/(12) = 1`

So,
`(4)/(12)+ (3)/(12)+ (5)/(12) = (12)/(12)` or 1.

Therefore 1 cup of flour was used that day.