X = cups of tea per hour
y = cups of coffee per hour
David makes 30 cups of tea per hour = 30x
David works for D hours this week.
Therefore number of weekly cups of tea = number of hours * cups of tea per hour
This is 30x * D = 30Dx
For Andrew, it is similar
30Ay
Because Andrew made an additional 10 cups, then it is 30Ay + 10
(cups of coffee this week)
-3x-4= +12
X negative 3 and 4 then add +12 to it.
I need to know what the questions are to answer this.
(39-7/4^2
32/16=2
I think the question is straight forward
The main formula is
M= P (i(1+i)^n) / <span>(1+i)^n) - 1
M: monthly payment
P: mortgage principale= </span><span> $20,230
i=montly interest, 11.5%=11.5/100=0.115, i= 0.115/12=0.009
n=number of months=12x20(years)=240 months
M= </span>$20,230(0.009(1.009)^240) / (1.009)^240-1=<span>$20,230 x 0.0077 / 8.58-1
M=$20.57
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