3. Miles of electric railway tracks (1915) were distributed as represented by the following line-graphs, where 1" represents 5000 miles. These numbers are not the exact numbers, but they are as near the exact numbers as you can get from the measurements made. Such numbers are often called "round" numbers (and sometimes "approximate" numbers). 4. The number of miles of railway tracks (1914) for certain states was as follows: Make line-graphs for these, letting 1" represent 5000 To get the nearest hundredth find out, by dividing, what the figure in the thousandths' place is. If that figure is 5 or more, the nearest hundredth is 1 higher than you get by dividing; if that figure in the thousandths' place is less than 5, the figure in the hundredths' place is not changed. 5. Represent the lengths of the following rivers by linegraphs, letting 1" represent 1000 miles. 6. Represent the heights of the following buildings in New York City by vertical line-graphs, letting 1" represent 200 feet. 7. Represent the heights of the following mountains by vertical line-graphs, letting 1" represent 5000 feet. 8. Represent the number of people speaking the following languages (1910) by horizontal line-graphs, letting 1" represent 50,000,000 people. 9. Represent by horizontal line-graphs the relative sizes of the following islands, using different scales for the CHAPTER IV PERCENTAGE DISCOUNT-INTEREST I. PERCENTAGE 42. Per cent means the number per hundred. Thus 96 per cent (written 96%) means 96 per hundred. For example, 96% attendance means that 96 of every 100 pupils are present. EXAMPLE 1. In a spelling test of 100 words, John spelled 96 correctly, or 96 per 100, or 96%; Mary spelled 92 correctly, or 92 per 100, or 92%; James spelled 88 correctly, or 88 per 100, or 88%; Henry spelled 84 correctly, or 84 per 100, or 84%. As there were 100 words in this test and per cent means per hundred, the number of words spelled correctly by each pupil gives also the per cent obtained by that pupil. EXAMPLE 2. In a spelling test of 25 words, John spelled 24 correctly, or or 96%; or 96 or 2 or 92%; or 88 100 8 or 88%; or 84 or 84%. Mary spelled 23 correctly, or 2 James spelled 22 correctly, or 2 Henry spelled 21 correctly, or John spelled correctly at the rate of 24 per 25 or 96 per 100; that is, John spelled 96% of the words correctly. Mary spelled correctly 23 of 25 (or at the rate of 92 per 100) and so spelled 92% (of the words) correctly. James spelled correctly 22 of 25 (or 88 per 100) or 88%. Henry spelled correctly 21 of 25 (or 84 per 100) or 84%. |