Question

Can you predict the outcome of multiplying 750 by 0.1 without calculating

Answer 1

Answer:

750 × 1/10  = 750/10 = 75

Step-by-step explanation:

The best way to really predict the outcome of multiplying 750 by 0.1 without calculator is firstly, converting the decimal to a fraction to easily do the multiplication in your head.

Since one of the multiplicand is a decimal the products will be much complicated therefore, to convert the decimal number 0.1 to a fraction number we shift the point to the right hand side which simply translate to 1/10.  The trick here is the number of times we shift the point will determine the number of zeros the denominator will possess.  Assuming we have 0.12 as the decimal, it is required we shift the point twice and the resulting value we become 12/100. If the decimal is 0.123 it is required we shift the point 3 times , the resulting value will be 123/1000. Not the number of times we shift the point will determine the number of zero's of the denominator.

Finally, the 2 multiplicands are now 750 and  1/10 which is more easier to manipulate in our head.  

750 × 1/10  = 750/10 = 75( you just cancel the zeros)