 |
|
|
|
|
|
|
|
|
An aircraft and a missile |
2006-11-18 |
|
From Sarah:
an aircraft is flying at a constant altitude with a constant speed of 600mph. an antiaircraft missile is fired on a straight line perpendicular to the flight path of the aircraft so that it will hit the aircraft at a point P. at that instant the aircraft is 2 miles from the impact point P the missile is 4 miles from P and flying at 1200 mph. at that instant, how rapidly is the distance between missile and aircraft decreasing?
Answered by Stephen La Rocque. |
|
|
|
|
|
|
Calculating volume of concrete, dirt, sand, anything. |
2006-11-17 |
|
From Debbie:
[This article contains a special calculator to help you find the volume (for example, the cubic yards) of material required to fill (or empty) a space if you know the length, width and depth.]
We are wanting to pour a 24'x30' slab that is 5" deep. How many cubic yards of cement do we need?
Answered by Penny Nom. |
|
|
|
|
|
|
Wheat is poured on a conical pile |
2006-11-17 |
|
From Rachel:
wheat is poured through a chute at the rate of 10 cubic feet per minute and falls in a conical pile whose bottom radius is always half the altitude. how fast will the circumference of the base be increasing when the pile is 8 feet high?
Answered by Penny Nom. |
|
|
|
|
|
|
My greatest digit is 9, ... |
2006-11-17 |
|
From Tiffany:
My greatest digit is a 9, but less than 900. I'm one more than a multiple of 10 and the sum of my digits is 12. Who am I?
Answered by Penny Nom. |
|
|
|
|
|
|
What percent of the people oppose putting in curbs? |
2006-11-17 |
|
From Dee-Dee:
The ratio of people who support putting in curbs to those who oppose it is 2 to 5. what percent of the people oppose putting in curbs?
Answered by Stephen La Rocque. |
|
|
|
|
|
|
The volume of a box |
2006-11-16 |
|
From Sam:
I have this box to mail and i would like to find out the cubic foot of the box.The W-52 -D-13- H- 37 inch cubic
Answered by Penny Nom. |
|
|
|
|
|
|
Induction |
2006-11-16 |
|
From John:
Find a formula for
1/(1x3)+1/(2x4)+1/(3x5)...+1/(n(n+2))
by examining the values of this expression for small values of n. Use mathematical induction to prove your result.
Answered by Penny Nom. |
|
|
|
|
|
|
Converting cubic meters to gallons and liters |
2006-11-16 |
|
From Lorne:
I have a large tank and I would like to know the formula for the conversion. And do you have any other info on web sites that have conversion tools as most of the tools are in u.s and I live in Canada and need the metric conversions.
Answered by Stephen La Rocque. |
|
|
|
|
|
|
The roots of a quadratic equation |
2006-11-16 |
|
From Lana:
If p and q are the roots of 2X^2 +3X+7=0, compute pq^3+qp^3. thanks for your help.
Answered by Penny Nom. |
|
|
|
|
|
|
Find the distance function s(t) given the acceleration function a(t) |
2006-11-16 |
|
From David:
Find the distance function s(t) of the acceleration function: a(t)= sin(0.1t)/ cos^3(0.1t)
Answered by Penny Nom. |
|
|
|
|
|
|
An equation for a line |
2006-11-16 |
|
From Jessica:
(-3,4) m=undefined write an equation for each line given the slope and a point on the line. show your work
Answered by Stephen La Rocque. |
|
|
|
|
|
|
How can half of 12 be 7? |
2006-11-16 |
|
From Liz:
How can half of 12 be 7?
Answered by Steve La Rocque, Chris Fisher and Penny Nom. |
|
|
|
|
|
|
What is the highest number possible with 3 digits? |
2006-11-16 |
|
From Liz:
What is the highest number possible with 3 digits? The teacher said the answer is not 999 and that the question did not say "3-digit number." My answer then is 9 to the 99th power (written mathematically of course) as this uses "3 digits" and is obviously a huge number. Is this correct?
Answered by Stephen La Rocque. |
|
|
|
|
|
|
The radius of an arch |
2006-11-15 |
|
From Kelly:
I am trying to achieve an arc height of .375 on the length of 17.375.
Answered by Penny Nom. |
|
|
|
|
|
|
Yards of concrete |
2006-11-15 |
|
From Tina:
How many yards of concrete to cover a 20 x 100 area 4 inches deep?
Answered by Penny Nom. |
|
|
