Answer:
She went on the slide 8 times and on the roller coaster 4 times
Step-by-step explanation:
We convert each statements to a mathematical equation.
Firstly, let's represent the number of times she went on the coaster with R and the number of times on the slide with S. We know quite well she went on 12 rides. Hence the summation of both number of times yield 12.
Mathematically, R + S = 12. ........(i)
Now we also know her total wait time was 3hours. Since an hour equals 60 minutes, her total wait time would equal 180 minutes.
To get a mathematical representation for the wait time, we multiply the number of roller coaster rides by 25 and that of the slides by 10.
Mathematically, 25R + 10S = 180 .......(ii)
Here we now have two equations that we can solve simultaneously.
From equation 1 we can say R = 12 - S. We can then substitute this into equation 2 to yield the following:
25(12 - s) + 10s = 180
300 - 25s + 10s = 180
300 - 25s + 10s = 180
300 - 15s = 180
15s = 300 - 180
15s = 120
S = 120/15
S = 8
S = 8 , and R = 12 - S = 12 - 8 = 4
<span><em />
3x+y=5</span>
<span /><span>2x-2y=22 ...............2(x-y)=22 ⇒ x-y=11</span><span><em /></span>
<span><em>3x+y=5</em></span>
<span /><span><em><u>x-y=11 </u> </em>(+)</span>
<span />3x+x+y-y=11+5
<span>4x=16 /:4</span>
<span /><em>x=4</em>
x-y=11
4-y=11
-y=7 /*(-1)
<em>y=-7</em>
<span><em></em></span>
A suitable calculator* can do this easily.
61°38'45" = (61 +(38 +45/60)/60)° ≈ 61.65°
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I like the RealCalc app for Android, but many graphing calculators also will do this conversion. Of course, you can simply evaluate the expression as above.
