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Divisibility by 3 |
2018-11-20 |
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From Ray: There is a rule that a number is divisible by 3 if the sum of its digits are divisible by 3 (for example, 81=8+1=9 {divisible by 3} and 33=3+3=6 {again, divisible by 3}) I know this works but I don't know why! Please help. Answered by Penny Nom. |
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Terry was two-thirds as old as Nia |
2018-11-19 |
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From Makenzy: four years ago, terry was two-thirds as old as nia. now terry is three-fourths as old as nia. how old is each now Answered by Penny Nom. |
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What was the original number? |
2018-11-18 |
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From jaydaleigh: Mark was thinking of a number. Mark adds 11 to it, then doubles it and gets an answer of 40.5. What was the original number? Answered by Penny Nom. |
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Percentage markup |
2018-11-17 |
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From Sher: Cost price is $32,500 and selling price was $ 85,495.25, what percent markup was made? Answered by Penny Nom. |
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2/5 as much time |
2018-11-16 |
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From Izzy: If Patricia spent 3/8 of her time cleaning her room. She spent 2/5 as much time
washing the dishes as she did cleaning her room. What fraction of time did Patricia
spend Washing dishes? And it wants us to simplify our answer Answered by Penny Nom. |
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-4 + 3/2 |
2018-11-15 |
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From Chloe: so I have this paper and I'm confused, -4 + 3/2=???? so I originally got -1/2 but I looked
at Calculator papa and he says -5/2 and then I looked at google and all I got was -2.5 and i
am so confused and lost. Answered by Penny Nom. |
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Price before VAT and a discount |
2018-11-15 |
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From Carol: I bought a computer for £330.
The selling price included VAT at 20%.
Then I was allowed a staff discount of £30.
What was it’s original price before the VAT and staff discount? Answered by Penny Nom. |
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The original cost when you only know a percentage |
2018-11-13 |
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From john: I was wonder how to find the Original cost when you don't know original cost
The amount paid was 13.82 that is suppose to represent 20%
because Insurance pays 80%
Thank You Answered by Penny Nom. |
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A line cuts a curve |
2018-11-11 |
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From roxanne: Hello, i need to ask a question, do you mind explaining and writing the formula of how to solve equations such as "find the set values of k for which the line y-2x-5 cuts the curve y=x^2 +kx+11" please Answered by Penny Nom. |
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The price of eggs rises 10 cents per dozen |
2018-11-10 |
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From Maddie: Hi! I'm currently struggling with a word problem that says:
"If the price of eggs rises 10 cents per dozen, one will be able to get 2 dozen fewer eggs with $6.00 than was possible at the lower price. What is the lower price?
We are working on completing the square and all of the problems I've done so far in this chapter require using that method. If possible and needed, could you explain how to set up the equation?
Thank you so much! I appreciate all your help!! Answered by Penny Nom. |
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Speed |
2018-11-06 |
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From Dolores: if I drove 3/4 mile in 32 seconds, what was my speed ? Answered by Penny Nom. |
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Dividing by a fraction |
2018-11-02 |
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From Fadely: If 8 divided by 4/2 can be expressed as 8 X 2/4, how can 8 X 2/4 be converted back to 8 divided by 4/2? Answered by Penny Nom. |
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Why 1/2 in the area of a circular sector? |
2018-10-26 |
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From Ariel: In the equation for area of a sector=1/2r^2theta why is it 1/2? Please explain conceptually not algebraically. Answered by Penny Nom. |
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Why 1/3 in the volume of a cone? |
2018-10-20 |
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From Keith: In the formula for the volume of a pyramid, Volume = 1/3 * base * height, where does the 1/3 come from, intuitively? Answered by Penny Nom. |
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f(x) and f(-x) |
2018-10-19 |
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From Simran: what is difference between f(x) compared to f(-x) on graph Answered by Penny Nom. |
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