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If the sum of digits of a number add to a multiple of 9, then the original number must be a multiple of 9.
You can multiply by nine on you fingers if the number is less than 10. Just hold up all your fingers (and thumbs) and put down the finger the represents the number you are multiplying. Lets say we want to multiply 7 by 9. Just put down finger 7. You will have 6 fingers to the left of finger 7 and 3 on the right, giving you 63. Or use 9. Put down finger 9, and you have 8 to the left and 1 to the right. Yes, 9 times 9 is 81.
The rule given at the top is why the finger trick works. You have 10 fingers, and if you put one down, you have nine. When multiplying any number between 1-10 by nine, adding the the digits of the product always gives nine - the same number as there are fingers left.
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What is 3 multiply 9?
3 multiply 9 = 27
What can you multiply to 5 to get 9?
The answer to the question of what can you multiply to 5 to get 9 is 4.
How do you turn Celsius into Fahrenheit?
-- take the Fahrenheit temperature -- subtract 32 from it -- multiply the result by 0.55 -- the result is the Celsius temperature This is another way. subtract 32 from the Fahrenheit temperature multiply by 5 divide by 9 (its just another way(i dunno if its faster or not XD))
What is 8 over 9 times 45?
The answer is 40. When you multiply 8/9 by 45, you first multiply the numerators (8 * 45 = 360) and then multiply the denominators (9 * 1 = 9). The answer is then 360/9, which simplifies to 40.
What two numbers multiply to get 9 and add to get 14?
23
What are multiples of 9 and 24?
Just multiply the two numbers to get it (which is, by the way,231)
What is the quick way to convert Fahrenheit to Celsius?
Celsius to Fahrenheit · Multiply by 9 · Divide by 5 · Add 32 Fahrenheit to Celsius · Subtract 32 · Divide by 9 · Multiply by 5
What is 3 multiply 9?
3 multiply 9 = 27
What can you multiply to 5 to get 9?
The answer to the question of what can you multiply to 5 to get 9 is 4.
9 oz is how many spoonfuls?
Measuring in Tablespoons you can just easily multiply the amount in Oz units like yours 9 Oz by 2 which means 18. So 9 Oz will consist of 18 Tablespoons.
What is the conversion 77f to c?
To convert F to C, subtract 32, then multiply by 5/9 77-32 = 45 45x5/9 = 25 Going the other way, to convert C to F Multiply by 9/5, then add 32
What is the multiple of Number 9?
There are an infinite number of multiples of 9! A multiple is what you get when you multiply something. The multiples of 9 are: 9, 18, 27, 36, 45, 54, 45, 63, 72, 81, 90, and so on, going up by 9 each time (forever). (1, 3, and 9 are FACTORS of 9, by the way - numbers that multiply to give 9)
How does 9 3 and 7 make 30?
One way is to multiply 3 and 7 in order to get 21 and then add 9 to 21 in order to get 30.
How do you turn Celsius into Fahrenheit?
-- take the Fahrenheit temperature -- subtract 32 from it -- multiply the result by 0.55 -- the result is the Celsius temperature This is another way. subtract 32 from the Fahrenheit temperature multiply by 5 divide by 9 (its just another way(i dunno if its faster or not XD))
What does multiply line 7 by 9 mean?
Multiply whatever number is on line 7 by 9.
What is the reverse of multiply by 9?
Divide by 9
What is 8 over 9 times 45?
The answer is 40. When you multiply 8/9 by 45, you first multiply the numerators (8 * 45 = 360) and then multiply the denominators (9 * 1 = 9). The answer is then 360/9, which simplifies to 40.
