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GCD |
2013-05-20 |
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From Julia:
Prove that if a and b are coprime integers, the greatest common divisor of a + b and a - b is either 1 or 2.
Answered by Penny Nom. |
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Inverse trig functions |
2013-05-19 |
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From ky:
hello, so iv'e been asked to draw a triangle with sides of 3, 4, and 5.
And find the measure of all three angle using sin-1, cos-1, tan-1.
I got really confuse, I'm taking the SAT pretty soon and it would be great
to get this... THANX
Answered by Penny Nom. |
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The square footage of a 17 inch by 17 inch tile |
2013-05-18 |
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From Leroy:
How do I calculate the square footage of a 17inch by 17 inch tile
Answered by Penny Nom. |
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(4- 4cos^4 x)/(sin^2 x) |
2013-05-18 |
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From Agnes:
How I can solve this question :
Simplify (4- 4cos^4 x)/(sin^2 x) and write in terms of sin x
Answered by Penny Nom. |
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r=10cos(t) in cylindrical coordinates |
2013-05-18 |
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From r.m:
question from calculus exam: what is the figure obtained having eqn.r=10cos(t) in cylinderical coordinates?
i know it is a cylinder with center (5,0) ,but can't the equation represent two cylinders ,one with center
(5,0) and the other with center (-5,0).
thanks for any help.
Answered by Penny Nom. |
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Inverting fractions and percentage |
2013-05-18 |
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From Carlos:
If I calculate the percentage change between two fractions, say,
1/100 and 2/100, I get 100% change. Now, if I flip denominator
and numerator, 100/1 and 100/2, and repeat the calculation, I
get a 50% change. Why are the percentages different?
Thank you very much
Answered by Penny Nom. |
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The percentage of fat in a container of yogurt |
2013-05-17 |
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From Katy:
There is a question that I' having trouble with. It says: "A container of yogurt
contains 228 g of water, 54 g of carbohydrates, 12 g of protein and
6 g of fat, what percentage of the yogurt is fat?" How do you convert 6 g
into percentage?
Answered by Penny Nom. |
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Cutting three sections of pipe |
2013-05-16 |
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From Michael:
A plumber cuts three sections of pipe from a 12’ length of ABS pipe, the lengths of the sections
are 33 3/8”, 56 5/8” and 39 7/8”. What is left over from the full length, if the saw cut is 1/8”
wide?
Answered by Penny Nom. |
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8 3/4 as a decimal |
2013-05-15 |
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From Luisa:
How to make 8 3/4 into a decimal
Answered by Penny Nom. |
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HCF and LCM |
2013-05-15 |
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From Kelly:
If HCF and LCM of two numbers is 7 and 20 respectively, then the number/s is/are….
Answered by Penny Nom. |
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Four digit combinations starting with 7 6 |
2013-05-15 |
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From Kaye:
How do I find the rest of a four digit combination starting with 7 6?
Answered by Penny Nom. |
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A circle and a chord |
2013-05-14 |
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From yashvardhan:
A circle which radius 13cm. Find the length of the chord which is 5 cm away from center
Answered by Penny Nom. |
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An equation in two variables |
2013-05-14 |
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From Steve:
Verify solutions to an equation in two variables. 4x-2y=8 (3, 2)
Answered by Penny Nom. |
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Dice |
2013-05-14 |
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From Julia:
What is the probability of rolling(as many times as necessary) a die and getting a total number(sum) when all the rolls are added together of 11?
Answered by Lorraine Dame. |
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A 2-digit number |
2013-05-13 |
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From A teacher:
Find a “2-digit number” where the sum of the 1st digit (on the Left)
and the square of the 2nd digit equal the same number.
Answered by Lorraine Dame, Harley Weston. |
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