Discover the Numeric Value of Y without a Calculator - Easy Methods!

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To find the numeric value of y in the equation y = 2.3*10^5 + 6.1*10^6 + 3.2*10^7 without a calculator, one can manage the zeros by converting each term to a common base of 10^5. This results in 2.3*10^5, 61*10^5, and 320*10^5, which sum to 383.3*10^5. The final result can be expressed as 3.833*10^7. Practicing similar problems can help develop shortcuts for quicker calculations. Mastery of these techniques can significantly reduce the time spent on each problem.
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Numeric value of y.

y = 2.3*105+6.1*106+3.2*107

Without calculator, how? '-'
 
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Er, what exactly are you having trouble with? (e.g. do you know how to compute 10^5?)
 


If i compute 105 and others:

32000000+6100000+230000 = 38330000

But if i have 50 questions like that and 1 hour to do all the questions? '-'

Don't have a easy way?

Sorry, my english is bad.
 


Such a test would still give you over an entire minute per problem!

If it takes you more than a minute to do a problem like this, (even without any shortcuts!) then you just need to practice.


I fully believe if you do a dozen or so practice problems, you'll start to see some short-cuts of your own -- e.g. shorthand for some parts of the numeral, or some parts of the answer you can just write down without having to do any computation at all.

I suspect these short-cuts are probably better figured out on your own than taught. e.g. I could tell you that you didn't really need to write down the last 4 0's of each number in your scratch work, but I doubt me telling you would have the same impact as you figuring a short-cut out yourself after working through enough exercises. It's almost always easier to use your own short-cut than somebody else's short-cut. (even if they are essentially the same thing)
 


MatheusMkalo said:
Numeric value of y.

y = 2.3*105+6.1*106+3.2*107

Without calculator, how? '-'

This can be an exercise in managing zeros:

2.3 * 10^5 = 2.3 * 10^5
6.1 * 10^6 = 61. * 10^5
3.2 * 10^7 = 320. * 10^5
Sum = 383.3 * 10^5 = 3.833 * 10^7
 
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