 | Charles Vyse - Arithmetic - 1806 - 342 pages
...Strokes do the Clocks of Venice (which go on to 24 o'Clock) strike in the Compass of a natural Day? (2) How many Strokes does the Hammer of a Clock strike in 12 Hours ? (3) The Length of my Garden is 94 Feet: now if Eggs be laid along the Pavement a Foot asunder, and... | |
 | Michael Walsh - Arithmetic - 1807 - 290 pages
...two extremes by the whole number of terms, the product is the total of all the terms. EXAMPLES. 1 . How many strokes does the hammer of a clock strike in 12 hours? 124-1 — !.? ;''"¡ 1 3 X 6=78 Ans. 2. A man buys 17 yards of cloth, and gave for the first yard 2i.... | |
 | Charles Vyse - Arithmetic - 1815 - 340 pages
...strokes do the clocks at Venice (which go on to 24 o'clock) strike in the compass of a natural day? (2) How many strokes does the hammer of a clock strike in 12 hours? (3) The length of a garden is 94 feet : now if eggs be laid along the pavement a foot asunder, and... | |
 | Thomas Keith - Arithmetic - 1822 - 354 pages
...the least term be 3, the greatest 108, and the number of terms 14, what is the sum of the terms? (3.) How many strokes does the hammer of a clock strike in 12 hours? (4.) If 100 stones be laid in a straight line, and exactly the space of a yard be left between one... | |
 | Warren Colburn - Algebra - 1825 - 400 pages
...equal, and one of them being multiplied by the whole number of terms will give the whole sum : thus if Hence, the sum of a series of numbers in progression by difference is one half the product of the number of terms by the sum ofthejirst and last terms. Example. How many strokes... | |
 | Thomas Dilworth - Arithmetic - 1825 - 218 pages
...of the extremes by the whole number of terms, the product is the total of all the terms. EXAMPLES. 1 How many Strokes does the Hammer of a Clock strike in 12 hours? Answer 78. 2 A merchant hath sold 100 yds. of superfine cloth, viz. the 1st yard for Is. the 3d 2s.... | |
 | Warren Colburn - Algebra - 1826 - 290 pages
...the terms are now equal, and one of them being multiplied by the whole number of terms will give the whole sum : thus Hence, the sum of a series of numbers...does the hammer of a clock strike in 12 hours ? a = 1, I = 12, and n = 12. S-_ 12 (1 + 12) _ ?8 ^n,. 78 strokes. 2 This formula and the following X _n(a... | |
 | Warren Colburn - Algebra - 1828 - 288 pages
...the terms are now equal, and one of them being multiplied by the whole number of terms will give the whole sum : thus Hence, the sum of a series of numbers...strokes does the hammer of a clock strike in 12 hours ? «=l, 1= 12, and M i= 12. S = 12 (l + 12) = 78. Ans. 78 strokes. In the formula I = a + (n — l)r;... | |
 | Warren Colburn - Algebra - 1828 - 292 pages
...of them being multiplied by the whole number of terms will give the whole sum ; thus 2 S = n (a + l) Hence, the sum of a series of numbers in progression...strokes does the hammer of a clock strike in 12 hours ? «=l, 1=12, and » = 12. o — 12 (1 -j- 12) — _s In the formula l = a + (n — l)r; substitute... | |
 | Nathan Daboll - Arithmetic - 1829 - 252 pages
...required the sum of the series. 23+3— 2(J sum of the extremes. Then 26 x 11-^2=14:3 the Answer. 2. How many strokes does the hammer of a clock strike in 12 hours. Aits. 78. 3. A merchant sold 100 yards of cloth, viz. the first yard for 1 ct. the second for 2 cts.... | |
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Hence, the sum of a series of numbers in progression by difference is one half of the product of the number of terms by the sum of the first and last terms. 
