In a certain lawn-mower factory, percent of all mowers produced are defective. On the average, there will be defective mowers out of how many produced?
We have a percentage problem on our hands.
We recall that 1% means 1 out of a hundred. If we had 0.1% – that implies that 0.1% is 0.1 out of a 100 and if we have 0.01% that means 0.01% is 0.01 out of a 100. How many times does 0.01 fit in 100? 100/0.01=10,000.
Now we have 0.06% or six times that number. This in-turn tells us we can expect to see 6 defective lawn mowers out of every 10,000. We observed only 3 such defective lawn mowers so we probably checked only half of 10,000 or 5,000 lawn mowers.
Another way to approach this question is to set up the equation were X stands for the number of lawn mowers.
100 (3/X) = 0.06% which is a single variable algebraic equation.