Formulas & shortcuts
Primary Maths · 20
Every formula in this course and the easiest ways to remember them, on one page.
1Numbers to 20Beginner
Numbers 0 to 20: counting and comparing
Open lessonAdding and subtracting to 20
Open lesson2Numbers to 100, money and timeBeginner
Numbers to 100: tens and ones
Open lessonAdding and subtracting to 100
Open lessonMoney and time
Open lesson3Multiplication and divisionIntermediate
Multiplication and the times tables
Open lessonDivision and word problems
Open lesson4Big numbers and column methodsAdvanced
Numbers to 1000 and beyond: column addition and subtraction
Open lessonMultiplying by one digit and dividing with a remainder
Open lessondividend = divisor × quotient + remainder
This is how we check a division with a remainder: 17 = 5 × 3 + 2.
5Measurement, shapes and fractionsAdvanced
Measuring: length, mass and capacity
Open lessonShapes and perimeter
Open lessonP = 2 × (a + b)
- Pthe perimeter of the rectangle
- athe length of the rectangle
- bthe width of the rectangle
P = 4 × a
- Pthe perimeter of the square
- athe side of the square