# I need some help on some of these, finding which fraction it would be with clues. I answered some, but some I need help on:

1. My numerator is 6 less than my denominator
I am equivalent to 3/4.

My answer to number 1: 6/12

2. My denominator is 5 more than twice my numerator

I am equivalent 1/3

3. The GCF of my numerator and denominator is 3.

I am equivalent to 2/5.

4.The GCF of my numerator and denominator is 5.

I am equivalent to 4/6.

5. My numerator and denominator are prime numbers.

My numerator is one less than my denominator

6.My numerator and denominator are prime numbers.

The sum of my numerator and denominator is 24.

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1. #1 - good
#2 - (assuming you don't know algebra)
make a list that match the description:
1/7 , 2/9, 3/11, 4/13, 5/15=1/3 , yeahhh
#3 - good
#4 - why not do what you did in #3, they are the same question.
however , if you picked 20/30 , the HCF would be 10 not 5
so the trick is to first reduce 4/6 to 2/3
now 2/3 -----> 10/15

notice the HCF of 10/15 is 5
and since 4/6 = 2/3 , and 10/15 = 2/3
4/6 <-----> 10/15

#5 no
the smallest prime number is 2, 1 is not considered a prime number, so you want

2/3

#6, the prime numbers are
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, ....
can you find a pair which adds up to 24 ?, then form the fraction

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2. #1 Huh? 1:6/12 = 12/6 = 2
How does that relate to what they said?
You need to set the words to math:

(d-6)/d = 3/4
4(d-6) = 3d
4d-24 = 3d
d = 24

check:
18/24 = 2/3
yes.

As with most skills, with a little practice it gets easier.
#2
n/(2n+5) = 1/3
3n = 2n+5
...

#3
Since 2 and 5 have no factors in common, just make sure 3 is a factor in the equivalent fraction
2/5 = 6/15
GCF = 3, so that works

#4
4/6 .. 4 and 6 do not have 5 as a factor, so
4*5/6*5 = 20/30
However, GCF(20,20) = 10
So, reduce the fraction first to get rid of other factors
4/6 = 2/3
2*5/2*5 = 10/15
Now GCF(10,15) = 5 and 10/15 = 2/3

#5
With one exception, all primes are odd numbers, which differ by at least 2. The only even prime is 2, so the fraction is 2/3

#6
You need two odd numbers whose sum is 24, and they are both primes. So, what are the choices?
3+21, no
5+19, yes
7+17 yes
9+15 no
11+13 yes
That's all we need to check - stop halfway there, because then we start getting repeat values.

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