Answer:
46% of Xander's friends prefer to stay home on Friday nights.
Step-by-step explanation:
Formula
As given
i.e
Zanders friends prefer to stay home on Friday night = 23
Total numbers of Zanders friends are 50.
Part value = 23
Total value = 50
Put in the formula
Percentage = 46%
Therefore 46% of Xander's friends prefer to stay home on Friday nights.
Answer:
The difference of the two means is not significant, so the null hypothesis must be rejected.
Answer:
98
Step-by-step explanation:
Add them all up. 60+20= 80+18 = 98.
The answer is: "
270 minutes " .
__________________________________________________________ → There are "
270 minutes" in "4 hours and 30 minutes" .
__________________________________________________________Explanation:__________________________________________________________Method 1):__________________________________________________________ Note: 60 minutes = 1 hour (exactly);
30 minutes =
? hr ? ;
→ (30 minutes) * (1 hr/ 60 minutes) ;
= (30/60) hr
= (3/6) hr
= (3÷3)/(6÷3) hr ;
= "
hr " ;
or; write as: "
0.5 hr " .
_________________________________________________________So "4 hours & 30 minutes" = 4 hours + 0.5 hours = 4.5 hours.
→ 4.5 hours
= ? minutes ;
The answer is: " 270 minutes" . 4.5 hours *
;
= (4.5 * 60) minutes
= "
270 minutes " .
→ The answer is: "
270 minutes ".
___________________________________________________________
Method 2) ___________________________________________________________ "4 hours and 30 minutes" =
<u> ? </u> minutes " .
___________________________________________________________→ " 4 hours
= <u> ? </u> minutes " ;
→ 4 hr . *
= (4 * 60) minutes
= 240 min. ;
→ There are " 240 minutes in 4 hours" .
→ To find the number of "minutes" in "4 hours and 30 minutes" ;
→ we takes the number of minutes in 4 hours—which is "
240 minutes"—and add "
30 minutes" to that number; as follows:
→ "
240 minutes + 30 minutes " ;
to get: "
270 minutes " .
_______________________________________________________ → There are "
270 minutes" in "
4 hours and 30 minutes" .
_______________________________________________________
The answer is: "
270 minutes " .
_______________________________________________________
General Idea:
If we have a quadratic function of the form f(x)=ax^{2} +bx+c , then the function will attain its maximum value only if a < 0 & its maximum value will be at x=-\frac{b}{2a} .
Applying the concept:
The height h is modeled by h = −16t^2 + vt + c, where v is the initial velocity, and c is the beginning height of the firecracker above the ground. The firecracker is placed on the roof of a building of height 15 feet and is fired at an initial velocity of 100 feet per second. Substituting 15 for c and 100 for v, we get the function as 
.
Comparing the function f(x)=ax^{2} +bx+c with the given function 
, we get 
, 
and 
.
The maximum height of the soccer ball will occur at t=\frac{-b}{2a}=\frac{-100}{2(-16)} = \frac{-100}{-32}=3.125 seconds
The maximum height is found by substituting 
in the function as below:
Conclusion:
<u>Yes !</u> The firecracker reaches a height of 100 feet before it bursts.
