There are 12 boys 21/7=3 so 4(3)= 12
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Step-by-step explanation:

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Answer:
For this scenario, I used the elimination method. Organize the equations, so it's easier to subtract from each other. My x-variable will represent the number of hot dogs and my y-variable will represent the number of sodas.
3x+2y=213
x + y =87
We need to make sure one of the monomials are alike in each equation, so we can eliminate a variable. Distribute 3 to each number/variable in the second equation.
3x+2y=213
3(x+y=87) --> 3x+3y=261
Now we can eliminate x.
3x+2y=213
- 3x+3y=261
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-y=-48
Divide -1 to both sides to get y=48. So, you sold 48 cans of soda. Now, we can find the number of hot dogs by substituting 48 into the second equation to get x+48=87. Subtract 48 to both sides to result with x=39. So, you sold 39 hot dogs.
Answer:
1.30
Step-by-step explanation:
2000^3.67 =1.3025071e+12
The slope of a function at a point is the value of its derivative there.
... f'(x) = 5·(2x) + 0 = 10x . . . . . . using the power rule: (d/dx)(xⁿ) = n·xⁿ⁻¹
Then
... f'(4) = 10·4 = 40 . . . . . the slope at x=4