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Selecting 3 students from 16 |
2010-03-09 |
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From amper:
A class has 12 boys and 4 girls. If three students are selected at random from the class,
what is the probability that they are all boys?
Answered by Penny Nom. |
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An irregular octagon |
2010-03-09 |
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From Gayle:
Question from Gayle:
I am building an irregular shaped octagon wooden box.
The measurements are 291/2 inches by 211/2 inches.
Sides are 12 inches.
It will be 36 inches high.
What would the cutting angles degrees be?
Answered by Harley Weston. |
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A trig identity |
2010-03-08 |
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From Kim:
I am having trouble proving this trig identity
(sin^2 x + 2 cos x-1) / 2+cos x - cos^2 x = 1/ (1+ sec x)
Answered by Penny Nom. |
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Log[f(x)] |
2010-03-08 |
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From sourabh:
What is the number of solutions of the equation
9 x 2 - 18 x + 5 = 0 for x, such that the expression
log10[(x+1)(x+2)] exists?
Answered by Harley Weston. |
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The side length of a square |
2010-03-08 |
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From tara:
am trying to help my brother's daughter in maths, tomorrow she has maths exam
1. Area of sq. picture is 441 sq.cm what is the length of its side.
Answered by Penny Nom. |
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0.999 ^ (500) |
2010-03-07 |
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From debra:
I just need to know how to solve the following problem without using a calculator: .999 ^ (500). I know the answer is .606, I just want to do it by hand since I can't use a calculator on my test.
Answered by Penny Nom and Claude Tardif. |
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The integral of X^3/the square root of 1-x^2 dx |
2010-03-07 |
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From William:
The integral of X^3/the square root of 1-x^2 dx.
Answered by Harley Weston. |
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Two overlapping circles |
2010-03-07 |
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From Hayden:
I have two circles of equal size. The radiuses of the circles are 30ft. The two circles are positioned 40ft apart and I need to find the area where they overlap.
Answered by Harley Weston and Tyler Wood. |
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Cooling |
2010-03-07 |
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From Lori:
If a house is always at 20 degrees celsius.
Water (tea) boils at 100 degrees celsius.
5 minutes later the tea was 70 degrees celsius.
Use an equation to predict the temperature after 20 minutes.
Answered by Tyler Wood. |
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Prove A intersect B =X iff A = X and B = X |
2010-03-06 |
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From Gloria:
how would you prove A intersect B =X iff A = X and B = X
Answered by Tyler Wood. |
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The line joining (3,4) and (-5,-6) |
2010-03-06 |
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From Patric:
Find the condition that the point (x,y) may lie on the line joining the points
(3,4) and (-5,-6)
Answered by Penny Nom. |
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The distance travelled by a minute hand |
2010-03-06 |
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From Patric:
How much distance will the minutes hand of length 14mm of a clock
cover in moving from 5 to 10?
Answered by Penny Nom. |
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Redwood Park and Glendale Park |
2010-03-05 |
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From Shaun:
Question from Shaun, a student:
Redwood and Glendale Parks are each surrounded by 100 yards of
fencing. The are of Redwood Park is 25 square yards more than the area
of Glendale Park. If both parks are rectangles, what is the measurement
of each rectangle?
Answered by Harley Weston. |
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How many people in total came to the museum that day? |
2010-03-05 |
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From simon:
1354 people attended exhibition A and 1427 people attended exhibition B. 79% of people attended both exhibitions. How many people in total came to the museum that day
Answered by Penny Nom. |
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Standard form |
2010-03-05 |
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From Laura:
How do I change 3y=4x+1 into standard Ax+By=C standard form. This is my son's schoolwork. I homeschool him. I got the answer to the problem as 3y=4x+1, but it needs to be written in standard form and I know it needs to read 4x-3y=-1, but how do I get that answer into standard form. I need to know how to explain it to him. Can you show me? Thank you so much.
Answered by Penny Nom. |
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