| James Hamblin Smith - Algebra - 1870 - 452 pages
...what scale is 5 1 1 1 73 written 572640 ? 7. Shew that a number in the Common scale is divisible : (1) by 3 if the sum of its digits is divisible by 3. (2) by 4 if the last two digits be divisible by 4. (3) by 8 if the last three digits be divisible by... | |
| Adolf Sonnenschein - 1873 - 194 pages
...derived from the Latin diyitus, a finger, the fingers being the natural counters. Learn by heart : A number is divisible by 3 if the sum of its digits is divisible by 3. NOTB. Every number divisible by 9 is divisible by 3 ; but not every number divisible by 3 is divisible... | |
| Richard Rickard - 1873 - 374 pages
...them are called their prime factors. 34. Test of divisibility : — Every even number is divisible by 2. A number is divisible by 3 if the sum of its digits be so divisible. A number is divisible by 4 if the number composed of the last two digits be so divisible.... | |
| Malcolm MacVicar - Arithmetic - 1876 - 412 pages
...sum of the digits is divisible by 9, the number 486 is divisible by 9 (Prop. II). PROP. XI. — Any number is divisible by 3, if the sum of its digits is divisible by 3. This proposition is shown in the same manner as Prop. X ; as 3 divides 10, 100, 1000, etc., with a... | |
| Robert Potts - Arithmetic - 1876 - 418 pages
...not divisible by 9 whoa the sum of the digits is not so divisible. As 9 is 3 times 3, it follows that a number is divisible by 3 if the sum of its digits be divisible Ly 3.1 Next, let the number 63547 be taken, and let it be divided intoparts which are... | |
| Edward Olney - Arithmetic - 1876 - 316 pages
...with an odd digit. 146. 1. It is possible that a number ending in any figure is divisible by 3. 2. Any number is divisible by 3, if the sum of its digits is so divisible, and not otherwise. DEM. — 1. There is no digit that may not be produced in the right-hand... | |
| Robert Potts - Arithmetic - 1876 - 392 pages
...not divisible by 9 wheu the sum of the digits ia not so divisiblo. As 9 is 3 times 3, it follows that a number is divisible by 3 if the sum of its digits be divisible Ly 3.1 Next, let the number 63547 be taken, and let it be divided into parts which are... | |
| Horatio Nelson Robinson - Arithmetic - 1877 - 250 pages
...number is divisible L By 2, if it is an even number. Thus, 20, 24, 36, and 44 are divisible by 2. 2. By 3, if the sum of its digits is divisible by 3. Thus, 135,471, and 1134 are divisible by 3. 3. By 4, if its two right-hand figures are ciphers, or... | |
| Edwin Pliny Seaver, George Augustus Walton - Arithmetic - 1878 - 370 pages
...number that is divisible by 2 is an even number; a number that is not divisible by 2 is an odd number. 2. A number is divisible by 3 if the sum of its digits* is divisible by 3. Thus, 285 is divisible by 3, for 2 + 8 + 5 = 15 is divisible by 3. 3. A number is divisible by 4 if... | |
| Edwin Pliny Seaver - 1878 - 376 pages
...shown above, the first part is divisible by 3. The other part is equal to the sum of its digits. Hence a number is divisible by 3 if the sum of its digits is divisible by 3. 14. The Greatest Common Factor of Numbers (Art. 175). The method of finding the gcf of numbers, as... | |
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