Step by step
The question
Question: U = 50(3)ʷ is the number of app users w weeks from now.
What does 3 mean?
We write the equation big, so we can label it.
1 What the letters mean
U is the number of app users.
w is the number of weeks.
It is the small raised number, the power: how many times we multiply by 3.
2 Make a small table
To see what each number does, we try a few weeks: 0, 1 and 2.
0 is where it starts.
w = 0: no weeks have passed, so we multiply by 3 zero times.
That is why 3 to the power 0 is 1.
50 times 1 is 50.
w = 1: 3 to the power 1 is just 3.
50 times 3 is 150.
w = 2: 3 squared is 3 times 3.
50 times 3 is 150.
Times 3 again: 150 times 3 is 450.
Look at the values of U: 50, 150, 450.
Each time w goes up 1, U is multiplied by 3.
The same number every time.
3 Find the numbers in the table
Now we write the equation again, and label its numbers.
50 is U at w = 0: the first number in the table.
So 50 is the number of app users at the start.
3 is what we multiply by, once for each week.
That is the power w: it counts the weeks.
Careful!
3 is multiplied, not added.
Look at the table: 50, 150, 450.
4 Say it in words
So 3 means: the number of app users triples each week.
Times 3 is triple.
5 Check
Let's check one more step: 150 times 3 is 450: the table at w = 2.
It works!
Let's look back.
First: what the letters mean.
Then: make a small table.
Then: find the numbers in the table.
Then: say it in words.
Last: check.