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Algebra Help Please!! (1 Viewer)

Tired of Study

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Okay I have no idea whatso ever with algebra......
Totally clueless. :confused:

Question is -

5 plain doughnuts and 6 iced doughnuts cost a total of $9.80. If each iced doughnut costs 50% more than a plain doughnut, found out the individual costs of a plain and an iced doughnut.

So far I have
5P + 6I = $9.80

Is this right?
 
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Let normal doughnuts = x
.: iced doughnuts = 1.5x

.: 5x + 6(1.5x) = 9.80
5x + 9x = 9.80
14x = 9.80
x = 0.70
.: normal doughnuts are $0.70
and iced ones are: 1.5(0.70) = $1.05
 

PC

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If you're studying General Maths, then you'll need to do this with only one variable.

So let's make p the cost of a plain doughnut.

Now the cost of an iced doughnut is 50% more, so the cost of an iced dougnut is 1.5 x p.

You know how to get the big equation now.
5 times the price of a plain doughnut plus 6 times the price of an iced doughnut is $9.80
Mathematically,
(5 x p) + (6 x 1.5p) = 9.80
5p + 9p = 9.80
14p = 9.80
p = 0.7
and from this 1.5p = 1.05

So a plain doughnut costs 70¢*and an iced doughnut costs $1.05
 
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hey can someone help me with this question?

Solve the equation which include roots and powers:

4r^3/3=36

thanks
 

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