| Gordon Augustus Southworth, John Charles Stone - Arithmetic - 1904 - 334 pages
...found by supposing the sectors to be triangles, that is, The area of a circle is the same as that of **a triangle having a base equal to the circumference and an altitude equal to the radius;** (^ x 7? or — - — times the unit of measure. £ 5. Find the area of a circle whose diameter is 10... | |
| John Henry Moore, George Washington Miner - Business mathematics - 1906 - 466 pages
...not exact triangles; but it is proved in geometry that the area of a circle is the same as that of **a triangle having a base equal to the circumference and an altitude equal to the radius.** ORAL EXERCISE 1. The base of a triangle is 8 in. and the height 11 in. What is the area ? 2. A field... | |
| John Charles Stone, James Franklin Millis - Arithmetic - 1910 - 440 pages
...found by supposing the sectors to be triangles; that is, The area of a circle is the same as that of **a triangle having a base equal to the circumference and an altitude equal to the radius.** 5. Cut a circle out of thick cardboard or sheet metal. Out of the same material cut a triangle whose... | |
| James Charles Byrnes, Julia Richman, John Storm Roberts - Arithmetic - 1913 - 552 pages
...divided into an infinitely large number of sectors, the figure ABCD tends to become a parallelogram, **having a base equal to ^ the circumference and an altitude equal to the radius.** FIG. 3. Area of parallelogram = base x altitude. Area of circle = ^ (circumference x radius), or ^(2... | |
| James Charles Byrnes, Julia Richman, John Storm Roberts - Arithmetic - 1913 - 468 pages
...into an infinitely large number of sectors, FIG. 2. the figure ABCD tends to become a parallelogram, **having a base equal to | the circumference and an altitude equal to the radius.** \C FIQ. 3. T Area of parallelogram = base x altitude. Area of circle = ^ (circumference x radius),... | |
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