A=2πrh+2πr2 Area of cylinder
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Answer:
okay so to figure out a perfect square a number has to be outlined by itself. 8 is not. 4 is because 2 times itself is 4. 81 is because 9 time itself is 81. 44 is not. 49 is because 7 times itself is 49. 125 is not. 150 is not. 144 is because 12 times itself is 144.
That is about coordinates and the dot product
we have a has coordinates (4;8)
and b has coordinates (-2;3)
So we have a.b= 4x(-2)+ 8x3= -8+24=16
The answer is 16
Answer:
9/20 mile
Step-by-step explanation:
Take (calculate) 3/4 of 3/5 mile:
3 3
---- * ---- = 9/20
4 5
9/20 mile needs to be repaved.
<h3>
Answer: 127</h3>
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Explanation:
The phrasing "2/3 of 4/5 of his 2nd exam on his 3rd test" is a bit clunky in my opinion. It seems more complicated than it has to be.
The student got 80 on the second exam. 4/5 of this is (4/5)*80 = 0.8*80 = 64. Then we take 2/3 of this to get (2/3)*64 = 42.667 approximately. If we assume only whole number scores are given, then this would round to 43.
Let x be the score on the fourth exam. Since 5 points of extra credit are given, the student actually got x+5 points on this exam.
So we have these scores
- first exam = 70
- second exam = 80
- third exam = 43
- fourth exam = x+5
Adding up these scores and dividing by 4 will get us the average
(sum of scores)/(number of scores) = average
(70+80+43+x+5)/4 = 80
(x+198)/4 = 80
x+198 = 4*80
x+198 = 320
x = 320 - 198
x = 122
So the student got a score of x+5 = 122+5 = 127 on the fourth exam.