Answer:
Sixth graders: 14
Seventh graders: 28
Eighth graders: 28
Step-by-step explanation:
To solve this you just have to use a rule of three to solve the percentages, remember that the 100% will be the 70 students, and we solve each case separetly:
70 students= 100%
sixth grades= 40%
Sixth grades= (40*70)/100
Sixth graders= 28
70 students= 100%
seventh grades= 20%
seventh graders= (20*70)/100
Seventh graders=14
So if we have that the rest of the students are eighth graders, we just add up the sixth and seventh graders and withdraw them from the total:
28+14=42
70-42=28
SOwe have that the eighth graders are 28
Answer:
Step-by-step explanation:
<em>a = 17</em>
<em>b = 18</em>
<em>c = 19</em>
- <em>Step-by-step explanation:</em>
<em>Hi there ! </em>
<em>a + b + c = 54</em>
<em>b = a + 1</em>
<em>c = a + 2</em>
<em>replace b ; c</em>
<em>a + (a + 1) + (a + 2) = 54</em>
<em>3a = 54 - 3</em>
<em>3a = 51</em>
<em>a = 51 : 3</em>
<em>a = 17</em>
<em>b = 18</em>
<em>c = 19</em>
<em>Good luck !</em>
Answer: 1/4 or 25%
Step-by-step explanation:
The chance of flipping tails is 1/2, so you multiply 1/2*1/2 (for the 2 flips) to get 1/4 (1/2^2=1/4).
