Answer:
x = 14.4
Step-by-step explanation:
x is sin(angle 24/30)×24
how do we get the angle at 24/30 ?
by using the extended Pythagoras for baselines opposite other than 90 degrees.
c² = a² + b² - 2ab×cos(angle opposite of c)
in our example the angle 24/30 is opposite of the side 18.
so,
18² = 24² + 30² - 2×24×30×cos(angle 24/30)
324 = 576 + 900 - 1440×cos(angle 24/30)
324 = 1476 - 1440×cos(angle 24/30)
1440×cos(angle 24/30) = 1152
cos(angle 24/30) = 1152/1440 = 576/720 = 288/360 = 144/180 = 72/90 = 36/45 = 12/15 = 4/5
angle 24/30 = 36.9 degrees
x = sin(36.9) × 24 = 14.4
Number of students who have sent a text message only is given by the difference between those that have sent a text message and those that have done both.
i.e. Number of students who has sent a text message only = 58 - 12 = 46
Number of students who have uploaded a selfie only is given by the
difference between those that have uploaded a selfie and those that
have done both.
i.e. Number of students who have uploaded a selfie only = 21 - 12 = 9
The total number of students surveyed is 70.
Let the number of students who have neither sent a text message nor taken a selfie today be x, then
46 + 9 + 12 + x = 70
67 + x = 70
x = 70 - 67 = 3
Therefore, 3 students neither sent a text message nor taken a selfie today.
The number of students that have sent a text message or have taken a selfie today is given by the sum of the number of students that have sent a text message and the number of students that have taken a selfie less the number of people that have done both.
i.e. number of students that have sent a text message or have taken a selfie today = 58 + 21 - 12 = 67.
Multiply 6 by 60 then divide by two which will get you 180.
Answer: 56 times.
Step-by-step explanation:
394/7 = 56.3
56 * 7 = 392
392 + 7 = 399
399 is more than 394, therefore the answer is 56.
