C. -7.78
Step-by-step explanation:
If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator . To do this, you need to find the least common multiple (LCM) of the two denominators. To add fractions with unlike denominators, rename the fractions with a common denominator. Then add and simplify.
Step 1: Keep the denominator the same. Step 2: Add or subtract the numerators. ...
Step 1: Find the Lowest Common Multiple (LCM) between the denominators. ...
Step 1: Convert all mixed numbers into improper fractions. ...
In this second method, we will break the mixed number into wholes and parts. ...
Thus, is equivalent to.
Fractions
Fractions can be thought of as another way of seeing division. If you have one whole pizza and two people want to share it equally, they will divide it into two halves:
The bottom number of a fraction is the denominator. It tells how many parts a whole has been divided into. In this case our pizza is divided into two parts.
Proper Fractions, Improper Fractions, and Mixed Numbers
A proper fraction is one in which the numerator is smaller than the denominator.
An improper fraction is one in which the numerator is larger than the denominator. If the numerator is larger than the denominator, the fraction equals a number that is greater than one.
Lowest Terms
Want to learn more? Take an online course in Basic Math.
Finding the GCF (Greatest Common Factor)
The greatest common factor is the largest factor that divides two numbers. We find this by figuring out what prime numbers are multiplied together to make up each number. A prime number is a number that can only be divided by itself or by one. Examples of prime numbers are 1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, etc. We want to focus on those that are less than ten in most cases.
Finding the LCD (Lowest Common Denominator)
Adding and Subtracting Fractions
To add or subtract two fractions, the two fractions must have the same denominator. Therefore, you will have to find the lowest common denominator and change each fraction to an equivalent fraction. Then you add or subtract the numerators as indicated and put the resultant number over the denominator and reduce the fraction to lowest terms.
