Let Ted be x.
Ed is 7 years older = x + 7
Ed = (3/4)Ted
(x + 7) = (3/4)x
x + 7 = 3x/4
x - 3x/4 = -7
x/4 = -7
x = -28, Ted = -28 years.
(x + 7) = -28 + 7 = -21, Ed = -21 years
Goodness. We had negative numbers for the ages, well does that make sense? No it doesn't.
Our answer is correct. But the sense in the question is lacking. The question has been wrongly set.
<span>We might assume negative ages to mean before they came into the world, before birth! </span>
The answer is: Find the mean of the differences with the other numbers in the set<span>. Add the squared differences and then divide the total by the number of items in </span>data<span> in your </span>set; t<span>ake the square root of this mean of differences to </span>find<span> the standard </span>deviation.
Green beans, cheese and hamburger
Answer

step by step Explanation
The functions given are


We want to find:

This implies that

Let us now simplify

This implies that

Combine the terms to get,

Because it is 5 units to the left of 3 on a horizontal number line