75% of 20 is 15
so she got 5 incorrect x
We can set up a system and solve it. Let these numbers be x and y. We can write that
and x-y=150. Combining these two equations, we can make a system of equations
. Solving this system, we find that x=400 and y=250
Answer:
0.2503
Step-by-step explanation:
To solve this , we use the Bernoulli trial equation.
Now, there are 10 questions with 4 options each. The total number of options is thus = 10 × 4 = 40 options
There are only 10 correct answers however. The probability of picking a correct answer is thus 1/4 or 0.25
Now we know there are 30 wrong options. The probability of picking a wrong option is 30/40 or 0.75
To answer 3 questions correctly, it means she would answer 7 wrongfully.
Now to complete the parameters for the bernoulli trial, we know she is making 3 correct choices. Now the number of ways to select three correct choices out of 10 is 10C3
Computing the Bernoulli trial, we have :
(10C3) × (0.25)^3 × (0.75)^10
= 0.2503
Answer:
Step-byThe equation of the line with slope 2 is y=2x+b, b is a constant which should be determined. The line passes via through points (1, 2) and (3,y)
(1, 2): 2=2+b --> b=0
So, the equation of the line is y=2x. Now, when x=3, y=6. So the line y=2x passes through points (1, 2) and (3, 6). (3,y)=(3, 6).-step explanation:
Answer: x(15x)
Step-by-step explanation:
