1. Say the reciprocal of the number is x.
Then:
1/2 + 3x = 1
3x = 1/2
/3 /3
x = 1/6
Since x is the reciprocal of a number, just flip it around to find the real number.
1/6 flipped = 6
So the number is 6.
2. So here we can look at the difference between 5 and 7, because even if you subtract 5 from both numerator and denominator the difference will stay the same.
It's two.
Now you want to find how much you have to multiply two by to get four.
2 * ? = 4
? = 2
So therefore you have to multiply the whole fraction by two to get a fraction with a denominator - numerator equal to 4
5/7 * 2/2 = 10/14
And then just subtract five from the numerator and denominator.
10 - 5 / 14 - 5
5 / 9 was the original fraction
