Answer: 20% of the teachers are from district M
There are 50 teachers from district M, so bar M is 50 units tall.
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Work Shown:
Let's add up the bar heights of the bars shown in the chart.
J+K+L+N = 50+80+30+40 = 200
So 200 teachers are from districts J,K,L, or N.
We're told that 250 total teachers attended. This must mean M = 50. We're effectively solving 200+M = 250.
So you'll need to draw a bar over M such that it is 50 units tall. This will complete the chart.
Because there are 50 teachers from district M, out of 250 total, we can then compute the percentage to get
50/250 = 0.20 = 20%
So 20% of the teachers are from district M.