 | Education - 1891 - 214 pages
...divisible by 5. 6. Any number whose last figure is 0 is divisible by 10. 7. Any number is divisible by 9 if the sum of its digits is divisible by 9. In all the earlier division work encourage promptness, even rapidity, but demand accuracy. Teach the... | |
 | Charles Austin Hobbs - Arithmetic - 1889 - 366 pages
...figures are zeros, or if the number expressed by them is divisible by 8. (7) A number is divisible by 9 if the sum of its digits is divisible by 9. (8) A number is divisible by 10 if its right-hand figure is 0. (9) A number is divisible by 11 if the... | |
 | David Martin Sensenig - Algebra - 1890 - 556 pages
...1 ; hence, с — с' = 0, or с = с'. 871. Cor. — In the decimal system, A number is divisible by 9, if the sum of its digits is divisible by 9. 872. Theorem IV. — If from a number, N, we subtract the digits of the even powers of r, and add those... | |
 | Eugene L. Dubbs - Arithmetic - 1893 - 238 pages
...divisible by 8. Thus, 4112 is divisible by 8, because 1 1 2 is divisible by 8. Any number is divisible by 9 if the sum of its digits is divisible by 9. Thus, 2574 is divisible by 9, because 2+5+7+4, or I^> is divisible by 9. LESSON II. Find the GCD of... | |
 | Webster Wells - Arithmetic - 1893 - 382 pages
...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... | |
 | 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... | |
 | Edwin Pliny Seaver, George Augustus Walton - Arithmetic - 1895 - 438 pages
...together are divisible by 8. Thus, 6728 is divisible by 8, while 6724 is not. 7. A number is divisible by 9 if the sum of its digits is divisible by 9. 8. A number is divisible by 11 if the sums of its alternate digits are equal, or if their difference... | |
 | 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... | |
 | 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 the... | |
 | 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... | |
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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. 
