mscroggs.co.uk
mscroggs.co.uk

subscribe

Sunday Afternoon Maths LV

Archive

Show me a Random Puzzle
 Most Recent Collections 

Tags

time geometry 2d shapes 3d shapes numbers spheres trigonometry complex numbers algebra lines graphs coordinates odd numbers fractions differentiation calculus folding tube maps ellipses triangle numbers money bases triangles squares area square numbers chess probability circles averages speed sport multiples dates factors parabolas functions logic cards games people maths shape prime numbers irreducible numbers probabilty angles proportion dice integration sum to infinity dodecagons hexagons multiplication factorials coins shapes regular shapes colouring grids floors integers rugby crosswords percentages digits sums rectangles clocks menace routes taxicab geometry remainders chalkdust crossnumber palindromes sequences means unit fractions division square roots surds doubling quadratics indices symmetry planes volume number partitions ave pascal's triangle mean advent arrows

Archive

Show me a Random Puzzle
▼ show ▼
 Posted on 2016-10-16 

Blackboard Sums

The numbers 1 to 20 are written on a blackboard. Each turn, you may erase two numbers, \(a\) and \(b\) and write the sum \(a+b\) in their place. You continue until only one number remains.
What is the largest number you can make?

Show Answer & Extension

Tags: Numbers

Two Tangents

Source: Reddit
Find a line which is tangent to the curve \(y=x^4-4x^3\) at 2 points.

Show Answer

Powerful Quadratics

Source: nrich
Find all real solutions to
$$(x^2-7x+11)^{(x^2-11x+30)}=1.$$

Show Answer

If you enjoyed these puzzles, check out Sunday Afternoon Maths LIX,
puzzles about regular shapes, or a random puzzle.
© Matthew Scroggs 2017