D. A cluster tells you where there is a concentration of data values.
To answer this you can use a guess and check strategy.
Start with 5 minutes using it (25% lost) and 10 minutes charging (20% gained).
Try 7 minutes using it (35% lost) and 14 minutes charging (28%).
Next, 9 minutes (45%) and 18 minutes(36%).
10 minutes (50%) and 20 minutes (40%). This is the difference.
She used it for 10 minutes and charged it for 20 minutes.
Answer:
(-4,9)
Step-by-step explanation:
To solve the system of equations, you want to be able to cancel out one of the variables. In this case, it'd be easiest to cancel out the x variables. To do this, you'll want to multiply everything in the first equation by 2 (2(x-5y=-49)=2x-10y=-98). Then, you can add the two equations together. 2x and -2x will cancel out, so you'll be left with -11y=-99. Next, solve for x by dividing both sides of the equation by -11, which will give you y=9. This is your y-coordinate! At this point, you're halfway to the answer as you just need your x-coordinate. It's not too difficult to find the x-coordinate, since you just substitute 9 into one of the equations. It doesn't matter which one you choose as you should get the same answer with both. I usually substitute the y-value into both equations, though, just to make sure I'm correct. Once you put the y-value into the equations, you should get x=-4 after solving it. :)
66 students can be expected to prefer the zoo.
<h2><u>Given</u> :</h2>
The given equations are :


Let's solve for g in equation (2) :


now, let's plug value of g from equation (3) into equation (1) :





plugging value of b in equation (3) :



since " g " represents ground seats, number of ground seats :
=》396
And " b " represents balcony seat, therefore it is equal to :
=》312
