Skip to main content

Take a look at our new Primary and Secondary
tasks open for students' solutions

Main navigation

Teachers
- Early years
- Primary
- Secondary
- Post-16
Students
Parents
- Early years
- Primary
- Secondary
- Post-16
Problem-Solving Schools
PD and Events
About NRICH

Search NRICH

Or search by topic

Number and algebra

Place value and the number system
Fractions, decimals, percentages, ratio and proportion
Calculations and numerical methods
Algebraic expressions, equations and formulae
Coordinates, functions and graphs
Patterns, sequences and structure
Properties of numbers

Geometry and measure

Vectors and matrices
Measuring and calculating with units
Pythagoras and trigonometry
Angles, polygons, and geometrical proof
3D geometry, shape and space
Transformations and constructions

Probability and statistics

Handling, processing and representing data
Probability

Working mathematically

Thinking mathematically
Mathematical mindsets

Advanced mathematics

Decision mathematics and combinatorics
Mechanics
Calculus
Advanced probability and statistics

For younger learners

Early years foundation stage

Solution

23524

Problem / game

Perfect Eclipse Back to problem

First name

Jongmin Lee

School

Nanjing International School

Country

Age

15

Filename

woocRF-JongminLee_Perfect Eclipse.zip

Footer

Sign up to our teacher newsletter
Technical help
Accessibility statement
Contact us
Terms and conditions

Links to the NRICH Twitter account
Links to the NRICH Facebook account
Links to the NRICH Bluesky account

NRICH is part of the family of activities in the Millennium Mathematics Project.