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Math in the universe 2015-01-21
From GA:
I want to find out examples in universe for this equation:
sin(x)/cos(x)=1 or tan(x)=1. I know the mathematical answer of pie/4 or 45 degree angle.

What I need to know is to find examples of this. I found an example in construction, for example, which is the shape of attic in the house.

I want to find examples in universe like in solar system, in quasars or jets coming out of them, in galaxies, in stars, in black holes, etc

Do you know of any such examples?

Answered by Robert Dawson.
The volume of a swimming pool 2015-01-21
From kirara:
Find the volume of water in a swimming pool with vertical ends and sides. The length measured at the water line is 50 ft. And the breadth is 20 ft. The bottom of the swimming pool is a plane sloping gradually downward so that the depth of the water at one end is 4 ft. And at the other end is 8 ft.
Answered by Penny Nom.
1,4,9,61,52,___ 2015-01-21
From Mubashir:
1,4,9,61,,52,___,84,___,18,1,121,___ please tell me its formula and also that rule that is being applied here like adding 3 or subtracting 5 etc.
Answered by Walter Whiteley.
The height of a building 2015-01-20
From Emily:
A man 2m high observes the angle of elevation to the top of the building to be 70 degrees. And the angle of depression to the bottom of the building to be 19 degrees. How tall is the building?
Answered by Robert Dawson.
Two cars 2015-01-18
From taylor:
two cars leave the park at the same time, one traveling north at a speed 10 mph faster than the other which is traveling south. after 3 hours the cars are 420 miles apart. find the speed of both cars
Answered by Penny Nom.
Pumping water from a borehole 2015-01-18
From patience:
An empty tank for storing water from a borehole has a volume of 480 cubic metres. If it is filled by a pump that pumps water at a rate of 16 litres per second, how many hours will it take the pump to fill this tank please show all calculations
Answered by Penny Nom.
1 + cot x divided by sin x + cos x 2015-01-15
From Torrie:
I need to solve this problem in terms of Sin, but I'm having trouble. 1 + cot x divided by sin x + cos x
Answered by Robert Dawson and Penny Nom.
Largest cone in a sphere 2015-01-15
From Alfredo:
What is the altitude of the largest circular cone that may be cut out from a sphere of radius 6 cm?
Answered by Penny Nom.
Percentage change 2015-01-14
From Jim:
When using a scale e.g. 0-10, what is the formula for calculating percentage change. For example when someone answers a questionnaire where a question has a 0-10 scale, and they score a 4 first time, and then they answer the same questionnaire a different day, and they score an 8, how do I calculate the percentage change.
Answered by Penny Nom.
A sequence 2015-01-13
From cyaz:
write a rule for each sequence then find next 3 terms for 7/8, 3 1/8, 5 3/8
Answered by Penny Nom.
An input/output table 2015-01-13
From Rose:
How do you create an input/output table when the rule is: the output is a +5?
Answered by Harley Weston.
$xx,xxx million 2015-01-12
From sherry:

as a financial editor, for years I've seen $\$$ amts like this:
$\$xx,xxx$ million (ie, with a comma, not dec point)
Isn't that thousands of millions, which would equal 'billions'?

Answered by Penny Nom.
An investment for 20 months 2015-01-12
From rose:
Darnell wants to have 2700$ to purchase a tv in 20 months. what will he need to deposit today if he earns 5% annual interest compounded monthly
Answered by Penny Nom.
h+h+h = -9 2015-01-12
From juanita:
How to solve h+h+h = -9
Answered by Penny Nom.
The length of a roll of paper 2015-01-12
From Peggy:
roll of paper 3ft wide and roll equals 500 sq ft how long would the roll be?
Answered by Penny Nom.



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