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### Course: 5th grade>Unit 4

Lesson 1: Strategies for adding and subtracting fractions with unlike denominators

# Estimating adding fractions with unlike denominators

Learn all about estimating the sum of fractions with unlike denominators. Practice visualizing fractions and using that understanding to make reasonable estimates when adding them together.

## Want to join the conversation?

• Oml! No matter how hard I try I CANT GET It !
• me too！this is so hard！
• Hi will you teach me more pls
• and for everybody who does not know when estimating you do not need to find the answer.
• The answer is an inpropper fraction. Its 22/15
• So the I just venerated it into
1 and 7/15
• it is so hard! really hard!
• it's so ez wdym??
• not really that hard tho
• how do you subtract them still i dont get it
• you don't
• its easy when you figure it out lol
• what is fractions and how can you solve fraction problems
(1 vote)
• Fractions are a way to represent parts of a whole or a collection of things. They are like slices of a pie! Here's how they work:

Numerator: The top number (e.g., 3 in 3/4) represents the number of parts you consider. Imagine you have a pie cut into 4 slices, and you take 3 of those slices.
Denominator: The bottom number (e.g., 4 in 3/4) represents the total number of parts the whole is divided into. In our pie example, the denominator is 4 because the pie was cut into 4 slices total.
Common types of fractions:

Proper fractions: When the numerator is smaller than the denominator (e.g., 3/4). The pie slices you consider (3) are fewer than the total slices (4).
Improper fractions: When the numerator is larger than or equal to the denominator (e.g., 5/4). This could represent having more slices (5) than the pie originally had (4), maybe you combined a whole pie with another slice.
Mixed numbers: A combination of a whole number and a fraction (e.g., 1 ½). Here, the 1 represents whole pies you have, and the ½ represents half of another pie.
Solving fraction problems:

There are four main operations we perform with fractions: addition, subtraction, multiplication, and division. Here's a quick guide:

Adding and subtracting fractions:

Fractions must have the same denominator (the number of slices must be the same size) before you can add or subtract the numerators (the number of slices you consider).
If the denominators are different, you need to find a common denominator, a least common multiple that both denominators can divide into evenly. Then, manipulate the fractions to have that common denominator and add/subtract the numerators.
Multiplying fractions:

Multiply the numerators and the denominators separately. (3/4) x (2/5) = (3 x 2) / (4 x 5) = 6/20
Dividing fractions:

Flip the second fraction (divisor) so it becomes its reciprocal (turn the numerator and denominator upside down). Then, multiply the two fractions like normal. (3/4) / (2/5) = (3/4) x (5/2) = 15/8
Tips for solving fraction problems:

Visualize: Use fraction models or draw diagrams to represent the fractions.
Simplify: Before and after calculations, try to simplify fractions to reduce terms with common factors (e.g., 6/12 can be simplified to 1/2).
Practice: The more you practice working with fractions, the more comfortable you'll become with the different operations.
Remember, fractions are a powerful tool for representing and working with parts of a whole. Understanding them unlocks problem-solving abilities in many areas of math and real-world applications.