Is the ratio 15:12 equivalent to these? No, it's not equivalent.
Why not? Because if we tripled everything in 5:3 then we'd get 15:9. We don't have the second value as 12.
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Is the ratio 30:18 equivalent to these? Yes it is equivalent
To go from 5:3 to 30:18, we multiply everything by 6
5*6 = 30
3*6 = 18
This shows that 5:3 scales up to 30:18
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Give two more examples of ratios that are equivalent to 5:3.
Pick any number you want. Let's say we pick 7. Multiply both parts of 5:3 by the value 7
5*7 = 35
3*7 = 21
The ratio 5:3 is equivalent to 35:21
The ratio 5:3 is also equivalent to 50:30 after multiplying both parts by 10.