Correct answer is C.
m + 3s = 50
the total number of questions is 20. since the paper is made of only multiple choice and short answer questions, the sum of the multiple choice and short answer questions should be 20.
since multiple choice is 'm' and short answer is 's'
then m + s = 20
but theres no option for that
if we take the number of points
points for 1 multiple choice question - 1
then points for m number of multiple choice questions = 1 * m = m
points for 1 short answer - 3
then points for s number of short answer question = 3 * s = 3s
then total number of points = m + 3s
and the total number of points = 50
therefore
m + 3s = 50
this is the correct answer C.
Let,
digital cameras be "x"
video cameras be "y"
Now,
According to the question,
5x + 3y = $3,213..................................................equation (1)
y = 4x..................................................................equation (2)
Taking equation (1)
5x + 3y = $3,213
Substituting the value of "y" from equation (2), we get,
5x + 3(4x) = $3,213
5x + 12x = $3,213
17x = $3,213
x = $3,213 / 17
x = $189
Taking equation (2)
y = 4x
Substituting the value of "x", we get,
y = 4 ($189)
y = $756
Now,
John buys a digital and a video camera. So, it costs him ($189 + $756) = $945
Answer:
The table is show clearly in the figure attached.
P(boy if favourite activity is swimming) = 8/17 = 0.47
P(girl if favourite activity is sport) = 7/27 = 0.26
P(girl if favourite activity is reading) = 4/6 = 0.67
P(boy if favourite activity is sport) = 20/27 = 0.74
P(favourite activity is swimming if a girl) = 9/20 = 0.45
P(favourite activity is reading if a boy) = 2/30 = 0.07
P(favourite activity is swimming if a boy) = 8/30 = 0.27
P(favourite activity is reading if a girl) = 4/20 = 0.2