Hope this helps you understand
An example for #1 would be that: 15 is divisible by 3, but not 9. every third multiple of 3, (9, 18, 27,...) is divisible by 9 because 9 is three times the size of 3.
For part two the first number that I thought of is 23.
1) Proportion a.
7 : 28 = 2 : 8
That means that the ratio 7 / 28 is equal to the ratio 2 : 8.
You can verify the equality by simplifying to the simplest form:
7 : 28 = 1 / 4 simplest form
2 : 8 = 1 / 4 simplest form, then the proportion is right.
In words that is 7 is to 28 as 1 is to 4 ← answer
2) Proportion b.<span>. 3⁄1 = 18⁄6
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</span><span>In words: 3 is to q as 18 is to 6 ← answer
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</span><span>You can verify the proportion by simplifiying the second fraction:
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</span><span> 18 / 6 = [18 / 6] / [ 6 / 6] = 3 / 1
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</span><span>3) Proportion c. 9 : 72 = 2 : 16
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</span><span>In words: 9 is to 72 as 2 is to 16 ← answer
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</span><span>Proove the proportion:
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</span><span> 9 / 72 = 1 / 8
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</span><span> 2 / 16 = 1 / 8
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</span><span>4) Proportion d. 81⁄9 = 45⁄5</span>
In words: 81 is to 9 as 45 is to 5 ← answer
Proove it:
81 / 9 = 9
45 / 9 = 9
0.3, 0.03,0.003
Because 0.3 is equivalent to 3/10
Because 0.03 is equivalent to 3/100
Because 0.003 is equivalent to 3/1000
