|
|
|
|
|
|
|
|
The units digit of a square |
2021-09-04 |
|
From Aarzu: Sorry this may be a dumb question but how do you find possible unit digits of a
perfect square Answered by Penny Nom. |
|
|
|
|
|
An arithmetic and a geometric sequence |
2021-08-29 |
|
From Moti: Let {an} be an arithmetic sequence such that its 1st, 20th, and 58th terms are
consecutive terms of some geometric sequence. Find the common ratio of the
geometric sequence. Answered by Harley Weston. |
|
|
|
|
|
Fibonacci numbers |
2021-08-25 |
|
From John: Make a single column of numbers. Start with two numbers of your choice.
The third number is the sum of the previous two, the fourth number is the sum of
numbers two and three, and so on until
you have ten numbers in the column. Add up all ten numbers. Now, take the
seventh number and multiply it by eleven. This product will equal the sum of the
ten numbers. The same result will occur regardless of the first two numbers
chosen.
The question is why does the 7th number multiplied by 11 always equal the sum of
the ten numbers? Answered by Penny Nom. |
|
|
|
|
|
A word problem |
2021-07-28 |
|
From Isaac: The average mass of a group of children is 50 kilograms. Todd, who has a mass of
62 kilograms, then joins the group. This raises the average mass of the group to
52 kilograms. How many children were in the original group Answered by Penny Nom. |
|
|
|
|
|
New pool liner |
2021-07-14 |
|
From Kareena: I have a rectangular prism shaped pond that are 4ft by 8ft by 2ft. My pond is
lined on the sides and bottom with a pool liner so that it doesn't leak (the top
of the pool does NOT have a liner). I am redoing my pool and would like to
increase the size of the pond. Each dimension will increase by the same amount,
and the size of the pool liner will double. How much I am increasing each
dimension of the pond? Give an exact answer and than an approx. answer rounded to
the nearest tenth. Answered by Penny Nom. |
|
|
|
|
|
How many ways can you travel from A to D? |
2021-07-02 |
|
From shawn: Hello, I am trying to solve a problem which is how many ways can you travel from
A to D. A has 4 options b has 3, C and you get to D. How many ways are there? Answered by Penny Nom. |
|
|
|
|
|
3.1 miles in 4 minutes |
2021-06-21 |
|
From Jean: I am a school bus driver. My route directions and time schedule have me traveling
3.1 miles in 4 minutes. How fast do "they" expect me to drive to accomplish this?
Thank You Answered by Penny Nom. |
|
|
|
|
|
UFO speed in MPH from nearest galaxy in one year |
2021-05-22 |
|
From Joe: If the next closest galaxy is 15 quadrillion miles away and there are 8760 hours
in one year; how fast would a UFO have to fly to travel from the next
galaxy, in MPH in one year ?
Google calculator gives this result: 1.7123288e+12
I don't understand what the "e+12" means.
How is that pronounced, ex. trillion, quadrillion etc..?
Answered by Harley. |
|
|
|
|
|
The diameter of an octagon |
2021-05-22 |
|
From Sue: What is the diameter of an octagon with 8 foot sides Answered by Penny Nom. |
|
|
|
|
|
The height of a cone |
2021-05-13 |
|
From Carmen: If a cone has a slant height of 25 inches and a radius of 7 inches what is the
height in inches of the cone? Answered by Harley Weston. |
|
|
|
|
|
2.5 percent of 1.5 billion |
2021-05-13 |
|
From Anish: What is the 2.5 percent of 1.5 billion?
please state if there are any general formulae of this calculation.
Thank you Answered by Penny Nom. |
|
|
|
|
|
An octagonal drum |
2021-05-11 |
|
From Louie: I teach carpentry on an Indian reservation.
My students want to make an 18 inch drum frame.
They want to have 8 sides or an octagon shape to the drum frame.
What angle I have to set my miter saw to cut the angles to fit the octagon together.
I want to use this formula by changing the diameter of the frame.
Answered by Harley Weston. |
|
|
|
|
|
More on a roll of paper |
2021-05-07 |
|
From Stephen: Can you help with the equations to calculate the length of paper required to
achieve a target outside diameter when wrapped around a core please?
The inside diameter of the cardboard core is 76mm
The thickness of the wall of the cardboard core is 5mm
The thickness of the paper is 138microns
The desired outside diameter of the finished roll is 320mm
I hope you can help me with a solution, Thank you Answered by Harley Weston. |
|
|
|
|
|
Word problem |
2021-05-07 |
|
From Donelle: Freddy is three times as old as Mary. Mary is twice as old as Jack. Jack is 11
years old. How old is Freddy? Answered by Penny Nom. |
|
|
|
|
|
The maximum area of a garden |
2021-04-28 |
|
From Lexie: suppose you want to make a rectangular garden with the perimeter of 24 meters.
What's the greatest the area could be and what are the dimensions? Answered by Penny Nom. |
|
|