Fractions Flashcards
Add, Subtract, Multiple and Divide Fractions. Fraction of a quantity. (16 cards)
Add 1 2/5 and 2 3/10
1 2/5 = 14/10
2 3/10 = 23/10
14/10 + 23/10 = 37/10
= 3 7/10
What is the lowest common multiple of 3 and 5.
3, 6, 9, 12, 15, 18
5, 10, 15, 20
So lowest common multiple is 15 (this is also the common denominator)
Find 2/3 of 45
Of means multiply. So
2/3 x 45 = (2x45)/3
=90/3 = 30.
2 1/3 - 5/6
Convert to improper fraction 2 1/3 = 7/3.
Find common denominator = 6.
7/3 = 14/6.
14/6 - 5/6 = 9/6 = 1 1/2
Convert 5/6 into a decimal and then into a percentage.
First step is to divide 5 by 6 using our calculators to get 0.8333. Then we multiply with by 100 to convert the decimal into a percentage. 0.8333 x 100 = 83.33%.
Convert 3/4 into a decimal.
We use our calculators and divide 3 by 4 to give 0.75.
1 1/4 - 7/8 =?
1 1/4 = 5/4
Find common denominator, 5/4 = 10/8
10/8 - 7/8 = 3/8
What is the lowest common multiple of 3 and 7?
3, 6, 9, 12, 15, 18, 21, 24
7, 14, 21, 28
So the lowest common multiple is 21 (3x7).
1 1/2 x 4/7
Convert to improper fraction. 1 1/2 = 3/2.
3/2 x 4/7 = (3x4)/(2x7)
= 12/14 = 6/7
Divide 1 3/4 by 2/3
1 3/4 = 7/4
7/4 div by 2/3 is the same as
7/4 x 3/2 = (7x3)/(4x2)
= 21/8 = 2 5/8
Add 3/4 and 5/6
Find a common denominator.
3/4 = 9/12 and 5/6 = 10/12
9/12 + 10/12 = 19/12 = 17/12
Divide 3 2/5 by 7/8
Convert to improper fraction. 3 2/5 = 17/5.
17/5 div by 7/8 is the same as
17/5 x 8/7 = (17x8)/(5x7)
=136/35 = 3 31/35
2 1/3 x 3/5 = ?
2 1/3 = 7/3
7/3 x 3/5 = (7 x 3) / (3 x 5)
= 21/15 = 1 6/15
Add 1/2, 3/5, and 3/10 together.
Find the common denominator = 10.
1/2 = 5/10 and 3/5 = 6/10.
so 5/10 + 6/10 + 3/10 = 14/10 or 1 4/10 or 1 2/5
Find 3/5 of 20.
When you see of it means multiply. 3/5 of 20 is the same as 3/5 x 20 = 12.
