| 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... | |
| Richard Rickard - 1873 - 372 pages
...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 conv A number is divisible by 8 if the number... | |
| 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 place by... | |
| 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,... | |
| 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... | |
| Robert Potts - Arithmetic - 1876 - 402 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... | |
| Edwin Pliny Seaver - Arithmetic - 1878 - 380 pages
...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... | |
| George Albert Wentworth, Thomas Hill - Arithmetic - 1881 - 446 pages
...number is divisible by 8 (2s) if the number denoted by the last three digits is divisible by 8. 4. A number is divisible by 3 if the sum of its digits is divisible by 3. 5. A number is divisible by 9 (32) if the sum of its digits is divisible by 9. 6. A... | |
| George Albert Wentworth, Thomas Hill - Arithmetic - 1882 - 376 pages
...number is divisible by 8 (2s) if the number denoted by the last three digits is divisible by 8. 4. A number is divisible by 3 if the sum of its digits is divisible by 3. 5. A number is divisible by 9 (32) if the sum of its digits is divisible by 9. ' 6.... | |
| Emerson Elbridge White - Arithmetic - 1883 - 370 pages
...divisible by 2 if its last digit is even. 2. A number is divisible by 5 if its last digit is either 5 or 0. 3. A number is divisible by 3 if the sum of its digits is divisible by 3. 4. If any prime number be divided- by 6, the remainder will be either- 1 or 5. .NOTE.—The... | |
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