Answer: 1. C) 5/18, 25/90
2. A) 6/10
Step-by-step explanation: 1) We need to find the ratios those makes a proportion:
Let us check given options one by one.
3/15, 12/55
Converting them into simplest fractions.
3÷3/15÷3 = 1/5
12/55 can't be reduce more.
1/5 ≠ 12/55
So, 3/15, 12/55 don't form a proportion.
8/24, 12/35
Converting them into simplest fractions.
8÷8/24÷8 = 1/3
12/35 can't be reduce more.
8/24 ≠ 12/35
So, 8/24, 12/35 don't form a proportion.
5/18, 25/90
Converting them into simplest fractions.
25÷5/90÷5 = 5/18
5/18 can't be reduce more.
5/18 = 5/18.
So, 8/24, 12/35 don't form a proportion.
So, 5/18, 25/90 form a proportion.
4/11, 16/25
Converting them into simplest fractions.
4/11 and 16/25 both can't be reduce more.
4/11≠16/25
So, 4/11, 16/25 don't form a proportion.
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Let us reduce 9/15 into simplest fraction.
9÷3/15÷3 = 3/5
Now, let us convert each and every option in simplest fractions.
6÷2/10÷2 = 3/5
16÷1/21÷1 = 16/21
36÷2/50÷2 = 18/25
45÷5/70÷5 = 9/14
We can see 6/10 gives lowest fraction 3/5 as 9/15 gives.
Therefore, 6/10 form a proportion with 9/15.