9 10 12 21
---- ---- ---- ----
12 15 16 28
Which of the following IS equivalent to 2/3?
2 6 9 10
--- ---- ---- ----
5 15 15 15
You can use cross-products to quickly select equivalent fractions.
Which of the following is equivalent to 1/5?
2 3 9 4
--- ---- ---- ----
5 15 15 20
Is 2/5 equivalent to 1/5?
Cross-product one: 5 x 1 = 5
Cross-product two: 2 x 5 = 10
NO.
Is 3/15 equivalent to 1/5?
Cross-product one: 3 x 5 = 15
Cross-product two: 15 x 1 = 15
YES.
Is 9/15 equivalent to 1/5?
Cross-product one: 9 x 5 = 45
Cross-product two: 15 x 1 = 15
NO.
Is 4/20 equivalent to 1/5?
Cross-product one: 4 x 5 = 20
Cross-product two: 20 x 1 = 20
YES.
Now you get to find a few equivalent fractions the way we learned a few lessons ago.
3 ?
--- = ---
4 8
Since 4 x 2 = 8, multiply the 3 by 2 to get 6.
3 6
--- = ---
4 8