 | James Alexander McLellan, Albert Flintoft Ames - Arithmetic - 1897 - 368 pages
...Walking on, B arrives at Q 2 hr. before A. Find the distance from P to Q. 243. A number is divisible by 9 if the sum of its digits is divisible by 9. Why ? 244. At what two times between 3 and 4 o'clock are the hands of a watch equally distant from... | |
 | Wilbur Fisk Nichols - Arithmetic - 1898 - 152 pages
...the units figure is 5 or 0. By 6, if it is divisible by 2 and 3. By 8, if the last three figures are divisible by 8. By 9, if the sum of its digits is divisible by 9. 13. Find the prime factors of 210. What prime number will divide 210? Divide by 2. What 2 ) 210 is... | |
 | Wilbur Fisk Nichols - Arithmetic - 1899 - 174 pages
...the units figure is 5 or 0. By 6, if it is divisible by 2 and 3. By 8, if the last three figures are divisible by 8. By 9, if the sum of its digits is divisible by 9. 13. Find the prime factors of 210. What prime number will divide 210 ? Divide by 2. What 2 ) 210 i8... | |
 | George Edward Atwood - Arithmetic - 1901 - 168 pages
...right-hand digits is divisible by 8, or if they are ciphers ; as, 24,720, 61,000, 23,048, 45,000, 21,768. By 9, if the sum of its digits is divisible by 9 ; as, 603, 828, 1008, 21,312, 73,305. FACTORING 37. Prime Factors are factors that are prime numbers.... | |
 | Eugene L. Dubbs - Arithmetic - 1901 - 462 pages
...right-hand figures is divisible by 8, or if it ends with three or more ciphers. 4. A number is divisible by 9, if the sum of its digits is divisible by 9. 78. To separate a composite number into its prime factors. What are the prime factors of 66 ? OPERATION... | |
 | William Estabrook Chancellor - Arithmetic - 1901 - 154 pages
...are divisible by 4. A number is divisible by 5 if its final digit is 5 or 0. A number is divisible by 9 if the sum of its digits is divisible by 9. 738 is divisible by 9, for 7 + 3 + 8 = 18, a number of which 9 is a factor. 117 is divisible by 9,... | |
 | William James Milne - Algebra - 1902 - 620 pages
...sum of the digits is divisible by that factor. 2. In the decimal system (a) Any number is divisible by 9, if the sum of its digits is divisible by 9. (b) Any number is divisible by 3, if the sum of its digits is divisible ЬуЗ. (c) Any even number... | |
 | William Estabrook Chancellor - Arithmetic - 1902 - 264 pages
...are divisible by 4. A number is divisible by 5 if its final digit is 5 or 0. A number is divisible by 9 if the sum of its digits is divisible by 9. 738 is divisible by 9, for 7 + 3 + 8=18, a number of which 9 is a factor. 117 is divisible by 9, for... | |
 | Wilbur Fisk Nichols - Arithmetic - 1903 - 296 pages
...the units figure is 5 or 0. By 6, if it is divisible by 2 and 3. By 8, if the last three figures are divisible by 8. By 9, if the sum of its digits is divisible by 9. 13. Find the prime factors of 210. What prime number will divide 210 ? Divide by 2. What 2 ) 210 ¡s... | |
 | John Williston Cook, Nebraska C. Cropsey - Arithmetic - 1903 - 408 pages
...Zealand. Prior to 1867 this line passed east of Alaska. 24. DIVISIBILITY BY 9. A number is divisible by 9 if the sum of its digits is divisible by 9. To understand this test examine the nature of the decimal 10 = 9 + 1. 20 = (2 x 9) + 2. 30 = 27 + 3.... | |
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An integer is divisible by 3 if the sum of its digits is divisible by 3. An integer is divisible by 9 if the sum of its digits is divisible by 9. 
