GB-31-02-001 · Missing value from mean
Five numbers have mean 19.4. Four of the numbers are 14, 4, 16, 43. Find the fifth number.
Averages: Reverse Mean ("TiMoNe")
Booklet p. 56
Method
1) Use TiMoNe triangle: Total = Mean × Number
2) Subtract the sum of the known numbers from the Total
Worked Example (GB-31-02-001)
1) Total of all five = 97.
2) 20
20