 | Webster Wells - Arithmetic - 1893 - 382 pages
...an even number, and the sum of its digits is divisible by 3. This follows from I and VI. VIII. Any number is divisible by 9 if the sum of its digits is divisible by 9. Thus, 864 is divisible by 9, because fhe sum of its digits, 18, is divisible by 9. IX. Any number is... | |
 | Edwin Pliny Seaver, George Augustus Walton - Arithmetic - 1895 - 412 pages
...is divisible by 2 and by 3. 6. A number is divisible by 8 if its hundreds, tens, and units together are divisible by 8. Thus, 6728 is divisible by 8, while 6724 is not. 7. A number is divisible by 0 if the sum of its digits is divisible by 9. 8. A number is divisible by 11 if the sums of its alternate... | |
 | Edwin Pliny Seaver, George Augustus Walton - Arithmetic - 1895 - 412 pages
...divisible by 9, and the other equals the sum of its digits. Every number can be so separated. Hence a number is divisible by 9 if the sum of its digits is divisible by 9. 3. Divisibility of numbers by 3. Any number that is divisible by 9 is divisible by 3. Therefore, when... | |
 | George Washington Hull - Arithmetic - 1895 - 404 pages
...if it is divisible by 2 and 3. By 8 if the number formed by its last three digits is divisible by 8. By 9 if the sum of its digits is divisible by 9. By 10 if the right-hand figure is 0. 13-21. Tell by inspection which of the following numbers are exactly... | |
 | James Alexander McLellan, Albert Flintoft Ames - Arithmetic - 1897 - 368 pages
...overtakes A in 4 hr. 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 the... | |
 | James Alexander McLellan, Albert Flintoft Ames - Arithmetic - 1897 - 368 pages
...overtakes A in 4 hr. 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
...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... | |
 | W. H. F. Henry - Questions and answers - 1899 - 440 pages
...divisible by 8, and not otherwise. (Demonstration similar to 108.) 113. W hen divisible by 9 f Any number is divisible by 9 if the sum of its digits is so divisible, and not otherwise. (For Demonstration, see Answer to Question 99, page 198.) 114. When... | |
 | Wilbur Fisk Nichols - Arithmetic - 1899 - 174 pages
...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... | |
 | William Estabrook Chancellor - Arithmetic - 1901 - 154 pages
...4, for 44, 88, and 24 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,... | |
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A number is divisible by 9 if the sum of its digits is divisible by 9. 
