Before viewing this page, it would be helpful to learn how to calculate Equivalent Fractions.
Mechanics working on some car engines use common fractions.
Many drill bits, sockets and Allen keys are in Imperial sizes such as 1⁄2 inch, 1⁄4 inch, 1⁄8 inch and so on.
Steps to add and subtract common fractions are:
Allen keys are used to measure gaps in car engines. Into a gap, Allen keys with thicknesses of 1⁄2 inch and 1⁄4 inch can fit. What is the width of the gap?
Answer:
1⁄2 + 1⁄4
= 2⁄4 + 1⁄4 (Steps 1 and 2)
= 3⁄4 (Step 3)
What is the width of a gap into which Allen keys with thicknesses of 3⁄8 inch and 1⁄16 inch can fit?
Answer:
3⁄8 + 1⁄16
= 6⁄16 + 1⁄16 (Steps 1 and 2)
= 7⁄16 (Step 3)
What is the total of 3⁄4 pizza and 2⁄3 pizza?
Answer:
3⁄4 + 2⁄3
= 9⁄12 + 8⁄12 (Steps 1 and 2)
= 17⁄12 (Step 3)
= 1 5⁄12 (Step 4)
There is 3⁄4 of a pizza. If I eat 2⁄3 pizza, how much is left?
Answer:
3⁄4 – 2⁄3
= 9⁄12 – 8⁄12 (Steps 1 and 2)
= 1⁄12 (Step 3)
Q1. 1⁄2 + 1⁄3
Q2. 3⁄4 + 1⁄3
Q3. 7⁄8 + 3⁄4
Q4. 5⁄6 – 3⁄8
Answers
A1. 5⁄6
A2. 1 1⁄12
A3. 1 5⁄8
A4. 11⁄24
Add 1 3⁄4 and 1 2⁄3.
Answer:
Change these mixed numbers to improper fractions first.
1 3⁄4 + 1 2⁄3
= 7⁄4 + 5⁄3
= 21⁄12 + 20⁄12
= 41⁄12
= 3 7⁄12
Q1. 2 1⁄8 + 3 3⁄4
Q2. 3 1⁄4 – 1 1⁄5
Answers
A1. 5 7⁄8
A2. 2 1⁄20
Bob loves to count. One day, his teacher put a pile of pencils on Bob's desk. Bob began to count the pencils. He told his teacher the following facts about the pencils:
How many pencils are there?
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