Answer:
15 seconds
Step-by-step explanation:
Because the split id 25% and 75%, we could create another average pretending that there are four kids, one who ran in 12 seconds, and three who ran in 16.
Equation for averages: (a₁ + a₂ + a₃ + ...
)/ n
Plug in:<em> (12 + 16 + 16 + 16)/4</em>
Add: 60/4
Divide: 15 seconds
Answer:
17.9
Step-by-step explanation:
3.7²+17.5²=319.94
= 17.9
<h2>Answer</h2>

Or as ordered pairs: 
<h2>Explanation</h2>
Lets solve our system of equations step by step
equation (1)
equation (2)
1. Solve for
in equation (2)

equation (3)
2. Replace equation (3) in equation (1) and solve for 




or
3. Replace the values of
in equation (3) and solve for 
- For 


or 
- For 



or 
So, the solutions of our system of equation are:

Hello!
Step 1: Simplify both sides of the equation.<span><span><span>
1.5<span>(<span>x+4</span>)</span></span>−3</span>=<span>4.5<span>(<span>x−2</span>)</span></span></span><span><span><span><span><span><span>
(1.5)</span><span>(x)</span></span>+<span><span>(1.5)</span><span>(4)</span></span></span>+</span>−3</span>=<span><span><span>(4.5)</span><span>(x)</span></span>+<span><span>(4.5)</span><span>(<span>−2</span>)</span></span></span></span>(Distribute)<span><span><span><span><span>
1.5x</span>+6</span>+</span>−3</span>=<span><span><span>4.5x</span>+</span>−9</span></span><span><span><span>
(<span>1.5x</span>)</span>+<span>(<span>6+<span>−3</span></span>)</span></span>=<span><span>4.5x</span>−9</span></span>(Combine Like Terms)<span><span><span>
1.5x</span>+3</span>=<span><span>4.5x</span>−9</span></span><span><span><span>
</span></span></span>Step 2: Subtract 4.5x from both sides.<span><span><span><span>
1.5x</span>+3</span>−<span>4.5x</span></span>=<span><span><span>4.5x</span>−9</span>−<span>4.5x</span></span></span><span><span><span>
−<span>3x</span></span>+3</span>=<span>−9</span></span>
Step 3: Subtract 3 from both sides.<span><span><span><span>
−<span>3x</span></span>+3</span>−3</span>=<span><span>−9</span>−3</span></span><span><span>
−<span>3x</span></span>=<span>−12</span></span>
Step 4: Divide both sides by -3.<span><span><span>
−<span>3x</span></span><span>−3</span></span>=<span><span>−12</span><span>−3</span></span></span><span>
x=<span>4
Hope this helps! Cheerio, and have a lovely day!</span></span>