Last time, I wrote a post about mathematics and money which started with some intermediate stuff like geometric series and eventually gave some hint at probability and numberical methods. And, I also wrote a post about
mathematics and a girl's tears explaining the basics of differential equations, which are considered as "advanced" by few people. This time, I'll be dealing with neither intermediate stuff, nor advanced stuff. I'll be dealing with something very basic and trivial. Hope you have fun reading this post.
When I see symbols like + - x / %, I see a lot of words. And some people see only those symbols. Through out this post, a statement is framed and represented twice...
Generally, Mathematical form takes less space. But, when some extra explaination is needed, I've added some extra lines. Hope you change the way you see the mathematical symbols after reading this post
5km + 5km = 10km
125kg - 75kg = 50kg
Since 120 > 30, walking requires more time.
Since 6 < 9, lunges give quicker results.
30 x 10km = 300km
6kg / 300km = 0.02 kg per km = 20 grams per kilometer
The percentage is ...
30/(15 + 30 + 15)
= 30 / 60
= 0.5 x 100%
= 50% efficiency
total weight lost by the 1st person = 20 - 5 = 15 kg
total weight lost by the 2nd person = 10 + 10 = 20 kg
weight-loss percentage of the 1st person = 15 / 100 = 15%
weight-loss percentage of the 2nd person = 20 / 100 = 20%
MEANING: When it comes to weight loss, the 2nd person has lost more weight due to dieting.
Now, fat loss..
original fat weight of both the people = 30% of 100kg = 30 kg
New fat weight of the 1st person = 30 - 20 = 10 kg
New fat weight of the 2nd person = 30 - 10 = 20 kg
changed weight of 1st person = 100 - 15 = 85 kg
changed weight of 2nd person = 100 - 20 = 80 kg
bodyfat percentage of the 1st person = 10 / 85 = 11.7% (approximately)
bodyfat percentage of the 2nd person = 20 / 80 = 25.0%
MEANING: Even though dieting resulted in more weight loss, dieting resulted in more than two times the fat!
E = mgh = 100 x 10 x 10 = 10,000 = 10 kilo Joules
Energy required to lift = mgh = 100 x 10 x 0.15 = 150 Joules = 0.15 kilo Joules
Energy spent by the muscles = 0.25 kilo Calories = 0.25 x (4.2 kilo Joules) = 1.05 kilo Joules
Efficiency of the muscles = work_done / energy_spent = 0.15 / 1.05 = 0.1428... = 15% (approximately)
Target calories = 2 kg of fat
= 2 x 7700 kilo calories
= 15,400 kilo calories in 30 days
= 513 kilo calories per day (approximately)
efficiency = work_done / energy_spent
=> 0.1 = mgh / energy_spent
=> energy_spent = mgh x 4
=> energy_spent = 100 x 10 x 0.15 x 10
= 1500 Joules
= 350 calories
= 0.35 kilo calories (approximately) per each stair.
=> energy spent in climbing up a floor of 20 stairs
= 20 x energy_spent in climbing up a stair
= 20 x 0.35
= 7 kilo calories
No. of floors = target_energy / energy_per_floor
= 513 / 7
= 73 floors (approximately)
MEANING: If that person climbs 73 floors a day, 2 kilograms of fat can be lost in a month.
Let the shooting starts in "t" no. of months from now. (t for time).
The weight equation of the 1st star would be .... weight = 100kg - 5kg x t months
The weight equation of the 2nd star would be .... weight = 70kg + 1kg x t months
These two are in the simultaneous linear equations form.
y = 100 - 5x
y = 70 + x
Solving these simultaneous linear equations, we get....
x = 5
y = 75
MEANING: In 5 more months from now, both those stars would weigh 75 kg.
FINALLY: The upcoming actor should transform his body from 85 kg to 75 kg. He has 5 months time to lose those extra 10 kg.
So... my dear fellow math enthusiasts, next time, when you see any student who says... "My interest is not in mathematics, but in acting/sports/something-else. I don't want to study mathematics"... Hope you would find posts like these useful in explaining why mathematics is important, irrespective of the career they are interested in.
I hope that such students would understand that there is a lot more hidden behind the boring/scary mathematical symbols they see! And try to understand how these mathematical symbols and concepts can be related to the field they want to pursue.