Subitising
Instantly recognizing the number of objects in a small group, without counting.
Example: knowing there are 5 coins here (without counting them).
- recurring decimal
- recursion
- recursive
- reduce
- reflection
- reflection symmetry
- reflex angle
- regrouping
- regular
- regular polygon
- regular polyhedron
- relative frequency
- relatively prime
- remainder
- remainder theorem
- rent
- repeating decimal
- result
- retail price
- revolution
- rhombus
- rhs
- right angle
- right triangle
- right-angled triangle