Step by step
The question
Question: what comes next?
100, 90, 80, 70, □.
100, 90, 80, 70, □
1 Find the jumps
2 Find the rule
Every jump is the same: −10.
The rule is: take away 10 each time.
= Rule: take away 10 each time
3 Use the rule
The number before the box is 70.
70 − 10 = 60.
70 − 10 = 60
So the next number is 60.
= 100, 90, 80, 70, 60
4 Check
We go one jump back.
60 + 10 is 70.
Yes!
It works.
60 + 10 = 70
Let's look back.
First: find the jumps.
Then: find the rule.
Then: use the rule.
Last: check.
Answer
= 100, 90, 80, 70, 60