Objective
Five locks, in order. Each code is a whole number from 100 to 999. You can retry a lock as many times as you need. A clean escape is every lock opened on the first try, with no hints.
KS3
Percentages of an amount, sharing in a ratio, solving ax + b = c, the area of a rectangle, and a missing number in a mean.
Foundation
Reverse percentages, brackets, enlargements, and expected frequency. The daily set is Foundation for everyone until midnight UK.
Higher
A percentage increase followed by the same percentage decrease, simultaneous equations, similar shapes, and area scale factors. Square the length scale factor before you scale an area.
Hints
Each lock has two hints. They show the method, not the code. Using one means that lock cannot count toward a clean escape.