Answer:
4 I guess
Step-by-step explanation:
Because
3-1=2
2^2=2*2=4
<span>The answer is c. 1.5r + 2.5(5 – r) = 10.50. Let r be the number of raisins and p be the number of peanuts. Raisins cost $1.50 per pound: 1.5r. Peanuts cost $2.50 per pound: 2.5p. Jeremy spends $10.50: 1.50r + 2.50p = 10.50. Jeremy makes 5 pounds of trail mix: r + p = 5. So, we have the system of two equations: 1.5r + 2.5p = 10.50 and r + p = 5. Use the second equation to express p: p = 5 - r. Now, substitute p in the first equation: 1.5r + 2.5(5 - r) = 10.50. Therefore, the correct choice is c. 1.5r + 2.5(5 – r) = 10.50.</span>
Answer:
20÷[18-{20-3(4)}]
120÷[18-[20-12]]
120÷[18-8]]
120÷10
12
Step-by-step explanation:

so, 13 of the 20 tables have 6 chairs each.
that means, the remaining 7 tables, have 4 chairs each.
13 * 6 = 78 chairs total for those 13 tables.
7 * 4 = 28 chairs total for the remaining 7 tables.
78 + 28, that's how many.
In order to solve this, you have to set up a systems of linear equations.
Let's say that children = c and adults = a
30a + 12c = 19,080
a + c = 960
I'm going to show you how to solve this system of linear equations by substitution, the easiest way to solve in my opinion.
a + c = 960
- c - c
---------------------- ⇒ Step 1: Solve for either a or c in either equation.
a = 960 - c
20(960 - c)+ 12c = 19,080
19,200 - 20c + 12c = 19,080
19,200 - 8c = 19,080
- 19,200 - 19,200
---------------------------------- ⇒ Step 2: Substitute in the value you got for a or c
8c = -120 into the opposite equation.
------ ---------
8 8
c = -15
30a + 12(-15) = 19,080
30a - 180 = 19,080
+ 180 + 180
-------------------------------
30a = 19,260
------- -----------
30 30
a = 642
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I just realized that there can't be a negative amount of children, so I'm sorry if these results are all wrong.