A Farmer's Wheat

Difficulty: Medium · Topics: Probability, Statistics, Standard Deviation

The line graph shows a farmer's wheat production (in tonnes) over five years.

graph "x":[-1.8,12.4],"y":[-1.1,7.5],"axes":false,"label":"Wheat production: 2007 40, 2008 30, 2009 80, 2010 40, 2011 60 tonnes","items":["type":"line","from":[1.786,0],"to":[1.786,6.0],"dash":true,"ink":true,"width":0.7,"type":"label","at":[1.786,-0.65],"text":"2007","italic":false,"type":"line","from":[3.571,0],"to":[3.571,6.0],"dash":true,"ink":true,"width":0.7,"type":"label","at":[3.571,-0.65],"text":"2008","italic":false,"type":"line","from":[5.357,0],"to":[5.357,6.0],"dash":true,"ink":true,"width":0.7,"type":"label","at":[5.357,-0.65],"text":"2009","italic":false,"type":"line","from":[7.143,0],"to":[7.143,6.0],"dash":true,"ink":true,"width":0.7,"type":"label","at":[7.143,-0.65],"text":"2010","italic":false,"type":"line","from":[8.929,0],"to":[8.929,6.0],"dash":true,"ink":true,"width":0.7,"type":"label","at":[8.929,-0.65],"text":"2011","italic":false,"type":"line","from":[0,2.25],"to":[10.0,2.25],"dash":true,"ink":true,"width":0.7,"type":"line","from":[0,3.0],"to":[10.0,3.0],"dash":true,"ink":true,"width":0.7,"type":"line","from":[0,4.5],"to":[10.0,4.5],"dash":true,"ink":true,"width":0.7,"type":"line","from":[0,6.0],"to":[10.0,6.0],"dash":true,"ink":true,"width":0.7,"type":"label","at":[-0.2,2.25],"text":"30","anchor":"w","italic":false,"type":"label","at":[-0.2,3.0],"text":"40","anchor":"w","italic":false,"type":"label","at":[-0.2,4.5],"text":"60","anchor":"w","italic":false,"type":"label","at":[-0.2,6.0],"text":"80","anchor":"w","italic":false,"type":"line","from":[0,0],"to":[10.5,0],"ink":true,"end":"arrow","type":"line","from":[0,0],"to":[0,6.6],"ink":true,"end":"arrow","type":"label","at":[10.6,0.35],"text":"Year","anchor":"e","italic":false,"type":"label","at":[0.1,7.0],"text":"Tonnes","anchor":"e","italic":false,"type":"polygon","points":[[1.786,3.0],[3.571,2.25],[5.357,6.0],[7.143,3.0],[8.929,4.5]],"closed":false,"ink":false,"width":2.6,"type":"point","at":[1.786,3.0],"ink":f