Three students had collected some data on the wingspan of some bats. Unfortunately, each student had lost one measurement. Can you find the missing information?
Can you number the vertices, edges and faces of a tetrahedron so
that the number on each edge is the mean of the numbers on the
adjacent vertices and the mean of the numbers on the adjacent
Ann thought of 5 numbers and told Bob all the sums that could be made by adding the numbers in pairs. The list of sums is 6, 7, 8, 8, 9, 9, 10,10, 11, 12. Help Bob to find out which numbers Ann was thinking of.
Most of you sent us the right answer to the
first question of the problem ('How many of 3kg and 8kg weights
would you need for the average (mean) of the weights to be 6kg?').
Some found it by trial and error, for example, Ellen from
Andy (Garden International School) pointed
Rosie from St Bartholomew's Cof E Primary
School gave us the answers to some whole-number averages in between
3 and 8:
A general solution was provided by Hyeon
(British School Muscat):
Hyeon also noticed something important from
the results of her trial with different weights:
Here are some of her trials: