The area of a rectangle is calculated as length times its width. So, for the given area above, the expression should b written as:
20 = LW
To know the length for various measurement of the width, we can write it by:
L = 20 / W
You can substitute any measurement to W and you can obtain the corresponding value of the length.
The 20th visitor will be the first to get both the key chain and the bumper sticker, I found this out by finding the least common multiple, or LCM, you do this by writing out the multiples of both 4 and 10, 4 8 12 16 20..... and 10 20 30... then you find the smallest number that both 4 and 10 have in common. I hope this helps, sorry if it doesn't.
The larger one is (-11 + 41)/2 = 15.
The smaller one is (-11 -41)/2 = -26.
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For two numbers a and b with sum s and difference d, you can write the equations
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Then adding the equations and dividing that sum by 2, you get
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You can subtract the second eqution from the first and get a similar result for the smaller number
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These are the formulas we used above.
Y = 5(3x)....y = total number of bowls and x = number of weeks
for 4 weeks......x = 4
y = 5(3*4)
y = 5(12)
y = 60...so the family will eat 60 bowls in 4 weeks