Well the first one is obtuse and more than 90 degrees, the 2nd one is also obtuse and more than 90 degrees, the 3rd one is acute and less than 90 degrees, the 4th one is obtuse and 180 degrees, and the 5th one is a right angle and is 90 degrees
So, Bob needs 2 cups of concentrate (I'll use the variable c to shorten it) for every 3.5 cups of water (w). When he has 6 cups of c, he has three times the original recipe, and therefore we need 3w as well.
3.5x2=6+1=7. So we need 7 cups of water.
Now, 6 cups of concentrate + 7 cups of water = 13 cups of orange juice.
Bob can make 13 cups of orange juice.
Hope I helped!
If you're looking for the simplified version of the fraction, you have to factor both numerator and denominator.
The numerator is actually already a prime number, so we're good
The denominator factors as 
So, a 3 appears in both numerator and denominator. We can simplify it:

If you want to compute the approximated value of this fraction, simply plug these values into some calculator to get

240 = 2 × 120
120 = 2 × 60
60 = 2 × 30
30 = 2 × 15
15 = 3 × 5
The 2, 2, 2, 2, 3 and 5 are all the prime factors of 240. So, 2^4 × 3 × 5
1500 = 3 × 500
500 = 5 × 100
100 = 5 × 20
20= 5 × 4
4 = 2 × 2
The 3, 5, 5, 5, 2 and 2 are all the prime factors of 1500. So, 2² + 3 + 5³