 | David Steel - 1805 - 392 páginas
...&c. are in arithmetical progression, decreasing by 4. PROPOSITION I. To find the sum of the series, multiply the sum of the extremes by half the number of terms. The product will be the answer. EXAMPLE 1. The sum of a number of terms, increasing by 3, the extremes... | |
 | George Willson - 1836 - 202 páginas
...first term of a series, the last term, and the number of terms being given, to find the sum. RULE. — Multiply the sum of the extremes by half the number of terms ; or, multiply by the whole number of terms, and take half the product. 1 . How many strokes does the... | |
 | George Willson - 1838 - 194 páginas
...first term of a series, the last term, and the number of terms being given, to find the sum. RULE. — Multiply the sum of the extremes by half the number of terms ; or, multiply by the whole number of terms, and take half the product. » 1. How many strokes does... | |
 | John Darby (teacher of mathematics.) - 1843 - 236 páginas
...the number of terms of a series of numbers in arithmetical progression toßnd their sum. RULE. — Multiply the sum of the extremes by half the number of terms, and the product will be the sum of the series. EXAMPLES. 1 . What is the sum of 2, 3, 4, 5, 6, 7, and... | |
 | George Hutton (arithmetic master, King's coll. sch.) - 1844 - 276 páginas
...multiply their sum by the number of terms ; and the product divided by 2 will be the sum of the series; or multiply the sum of the extremes by half the number of terms, and the product will be the sum of the series. EXAMPLES FOR PRACTICE. fi the last term 29, and the... | |
 | Benjamin Greenleaf - 1849 - 336 páginas
...extremes by the number of terms, and half the product will be the sum of the series. Or, RULE II. — Multiply the sum of the extremes by half the number of terms, and the product is the sum required. EXAMPLES FOR PRACTICE. 1. If the extremes of a series are 5 and... | |
 | Rufus Putnam - 1849 - 402 páginas
...multiplied by the number of terms. Hence the following RULE. Find the lost term as in Case I., and then multiply the sum of the extremes by half the number of terms. Or, Multiply the sum of the extremes by the number of terms, and take è the product. 8. How many times... | |
 | Uriah Parke - 1849 - 414 páginas
...plain that this is double the sum of one series. Hence to find the sum of an arithmetical series " Multiply the sum of the extremes by half the number of terms" or what amounts to the same, half the sum of extremes by the number of terms. The latter is equivalent... | |
 | Uriah Parke - 1850 - 402 páginas
...plain that this is double the sum of one series. Hence to find the sum of an arithmetical series " Multiply the sum of the extremes by half the number of terms" or what amounts to the same, half the sum of extremes by the number of terms. The latter is equivalent... | |
 | Horatio Nelson Robinson - 1850 - 256 páginas
...first term. A rule for finding the sum of any series, we draw from equation (-B), thus : RULE . — Multiply the sum of the extremes by half the number of terms. EXAMPLES. 1. The first term of an arithmetical series is 5, the last term 92, and the number of terms... | |
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Multiply the sum of the extremes by half the number of terms, and the product is the sum required. 
