Although the concept here is physics, the solution is technically just algebra. You have two situations that are related to each other which can be expressed in equation form. Actually, the equation is already given which is <span>7/12 w= 13 5/12. So, basically, all you have to do is solve for w.
Let's simplify 13 5/12 first into an improper fraction.You do this by multiplying the denominator with the whole number and adding to it the numerator. This will be your new numerator, The denominator would still be 12. So, this is equal to (12*13 + 5)/12 = 161/2. Then,
(7/12) w = 161/12
By cross multiplication,
7*12*w = 161*12 w = 161/7 = 23
Therefore, w = 23 pounds which is the weight of the object on Earth.
The normal rule to remember is 68-95-99.7, i.e. plus or minus three sigma corresponds to 99.7% of the probability. That leaves 0.3% in the two tails, or 0.15% in the tail above 3 sigma.
