Ha. That looks alot like i-ready. (i-ready sucks butt.)
But the horror that is i-ready aside, your answer is the third one : The proportion of grandparents that feel safe entering their account information online is 0.32.
32% converted to a decimal is 0.32, and 68% converted to a decimal is 0.68. That would mean that the proportion for grandparents that feel safe doing so is 0.32, and the number of grandparents that don't feel safe doing so is 0.68.
The rule would be addition. (+300)
Answer:

Step-by-step explanation:
First, let's start with what we have. If we use
here's what we can put in:

Then we can use one of the given points to find the y-intercept. Since the only complete one is (12,10), we'll use that.

So now we have
.
Now we can use our other point with the missing y-value and solve for y.

So the missing value is 64.
Hope this helps!