Two rules, two patterns
The question
Two rules, two patterns
row 1:5→30
row 2:10→60
row 3:15→90
row 4:20→?
row 1:5→30
row 2:10→60
row 3:15→90
row 4:20→?
row 1:5→30
row 2:10→60
row 3:15→90
row 4:20→?
row 1:5→30
row 2:10→60
row 3:15→90
row 4:20→120
- Each row pairs a left number with a right one, and the same rule links them on every row.
- Read the link off a row with nothing missing. Row 1: 5 on the left, 30 on the right — that is × 6.
- The same link holds all the way down, so use it on the gap: 20 × 6 = 120.
- Counting down the column gives the same answer — a good check.
How it works.
- 01
Each row pairs a left number with a right one, and the same rule links them on every row.
- 02
Read the link off a row with nothing missing. Row 1: 5 on the left, 30 on the right — that is × 6.
- 03
The same link holds all the way down, so use it on the gap: 20 × 6 = 120.
- 04
Counting down the column gives the same answer — a good check.