Let's begin by calling Sarah's age now as X. As Ralph is 3 times as old as Sarah, X times 3 = 3X. Hence, Ralph's age is 3X. In six years, Ralph will be twice as old as Sarah. To calculate six years from now, add 6 to X for Sarah, and 6 to 3X for Ralph. As Ralph is twice as old as Sarah and we want to find the difference between the ages to calculate X, multiply X+6 by 2. You'll get 2X+12. Therefore, 2X+12=3X+6. Deduct 6 from 3X+6 as we want to isolate the variable. Because you did that to one side, you have to deduct 6 from 2X+12. Hence, now you have 2X+6=3X. X=6. Ralph's age is 3X, so 6 times 3 is 18. Ralph is 18 years old.
This is asking what is z and y, so you must know that a triangle is 180 degrees, so if it is 180 degrees, than all three angles that the triangle has must add up to 180 for every single triangle for it to be a triangle. So you have 45 degrees and 47 degrees, which adds up to 92 degrees, so in order to find y you need to subtract 92 from 180, which is 88. 88 is the missing number, and the missing number in this triangle is y, so y= 88 degrees. This can fool you because it looks like 90 degrees, but it is actually 88. Z is a little trickier, because y isn't 90 degrees, if it was than z would be a direct reflection of y, but it isn't, so we must find the exact angle for this variable. I see it like this, if y is 88, than it is smaller than 90 obviously, so it is acute. If that line keeps going down, than really z would be bigger than y, because that line is going down but it is so hard to tell. So if y is smaller by 2 degrees, than z would be bigger by 2 degrees, meaning that z is 92 degrees, since it is slowly decreasing. Hope this helps
The ratio would be written as 2:3 because there are 2 girls for every 3 boys