Numbers & Arithmetic

21 interactive Mathematics simulations on numbers & arithmetic.

Surds – simplifying, adding, multiplying and rationalising the denominator Mathematics · Numbers & Arithmetic Pick n and see √n split as a√b using the largest square factor: a square of area n is made of a × a small squares of... Ages 14–15
Square Roots and Cube Roots – Side of a Square and a Cube Mathematics · Numbers & Arithmetic A square with area S has side √S; a cube with volume V has side ∛V. Drag the square's corner or the cube's vertex to... Ages 14–15
Square Roots on the Number Line – Construction and Approximation Mathematics · Numbers & Arithmetic Construct √2 as the diagonal of a unit square, then chain right triangles with leg 1 to build √3, √4, … √n (the... Ages 12–13
Unit conversion – ratio tables, area, volume and compound units Mathematics · Numbers & Arithmetic Convert length, mass, time, capacity, area and volume on a unit ladder and a ratio table by multiplying by a... Ages 12–13
Equivalent fractions – balance scale matching game Mathematics · Numbers & Arithmetic A card game: drag cards (numbers or shaded pictures: circles, rectangles, rows of hexagons) onto the two pans of a... Ages 11–12
Mixed numbers – pictures, number line and practice game Mathematics · Numbers & Arithmetic The Intro screen uses two spinners to set the numerator and denominator and shows the improper fraction or the... Ages 11–12
Standard form A × 10ⁿ – moving the decimal point, scale of the universe and calculations Mathematics · Numbers & Arithmetic The Convert screen places a number in a place-value table (10³, 10², …, 10⁻³), expands it as a sum of digit × power... Ages 12–13
Rounding decimals on a number line Mathematics · Numbers & Arithmetic A decimal number sits on two number lines: the top one is marked off by the rounding place, and the bottom one zooms... Ages 11–12
Percentages with a bar model – parts, wholes, multipliers and compound interest Mathematics · Numbers & Arithmetic On the Percentage bar screen, drag along a bar split into equal parts or across a 10 × 10 grid to find p% of an... Ages 11–12
Equivalent fractions – multiplying top and bottom, with a game Mathematics · Numbers & Arithmetic Split a circle or a long bar into equal parts and shade some of them to make a fraction, then multiply both the... Ages 11–12
Fractions – a visual introduction Mathematics · Numbers & Arithmetic Build a fraction with circles, bars, cups of water, cakes or a number line: drag pieces from the bucket into a shape... Ages 11–12
Fraction models – compare, add, multiply and divide Mathematics · Numbers & Arithmetic Two fractions are shaded on a bar or circle model. Tap the parts to change the numerator and use the buttons to... Ages 11–12
Sieve of Eratosthenes – finding prime numbers Mathematics · Numbers & Arithmetic A grid of numbers from 1 to N. Each time you click 'Next step', the smallest unmarked prime is highlighted in blue... Ages 11–12
Multiplying decimals – area model Mathematics · Numbers & Arithmetic Drag two sides of a rectangle to change two decimal factors; the rectangle is split into ones, tenths and... Ages 11–12
Order of operations – brackets, powers, × ÷ and + −, step by step Mathematics · Numbers & Arithmetic Step through an expression with brackets, powers, ×, ÷, + and − while its expression tree fills in from the bottom,... Ages 11–12
Adding and subtracting integers on a number line Mathematics · Numbers & Arithmetic A number line with two arrows: the blue arrow goes from 0 to a, and the red arrow continues b steps further (to the... Ages 11–12
Rational numbers on a number line – comparing and zooming in Mathematics · Numbers & Arithmetic Two rational numbers a and b (entered as p/q or a decimal) are marked on a number line; the zoomed-in axis below is... Ages 12–13
Number line – distance and absolute value Mathematics · Numbers & Arithmetic Two screens: Situations places two points in three familiar contexts (two houses on a street, temperatures during a... Ages 12–13
Number line – operations with integers Mathematics · Numbers & Arithmetic Three screens explore adding and subtracting integers through money: Chips shows each +1 saving or −1 debt as a chip... Ages 11–12
Number line – integers Mathematics · Numbers & Arithmetic Two points A and B can be dragged along a number line to read and compare integers. The Situations screen links... Ages 11–12
Community Chi-square tests: goodness of fit and independence Mathematics · Numbers & Arithmetic Switch between a goodness-of-fit test and a test of independence. Edit observed counts for a die-style experiment or...