If the number of hours in school each week is somewhere between 20 and 40, then it can be written in scientific notation as
2.0×10¹ to 4.0×10¹
The exponent of 10 in each case is 1, so we can say the Order of Magnitude is 1.
TRUE
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In Engineering terms, the order of magnitude is sometimes considered to be the integer part of the base-10 logarithm of the number.
log(20) ≈ 1.3010
log(40) ≈ 1.6021
If we round these numbers to integers, we find the order of magnitude of the first is 1; the order of magnitude of the second is 2. Thus a student who spends 6 hours per day for 5 weekdays in class will have hours with an order of magnitude of 1, while a student who spends 7 hours per day for 5 days each week will have hours with an order of magnitude of 2. This question is best answered by considering "order of magnitude" in the simplistic terms of the answer above: the exponent of 10 in scientific notation.
Remember,
To subtract 2/3-1/2 you have to make them equivalent
2/3×2-1/2×3 = 4/6 - 3/6=
1/6
