Answer:
240
Step-by-step explanation:
We know that 50% of the number is 150 so we can assume the number is 300(if its 50% just double that number). Next we use the equation 0.80 x 300 which gives us the answer 240.
Hope I helped
The mean is the best measure to summarise the scores.
Answer:
The correct option is D.
Step-by-step explanation:
The given equation is

According to the addition property of equality
and
are equivalent equations.
Use addition property of equality, add 3x on both the sides.


Therefore Sam's work is incorrect because he make calculation mistake.
According to the subtraction property of equality
and
are equivalent equations.
Use subtraction property of equality, subtract 5x from both the sides.


Therefore Roy's work is correct because he used subtraction property.
Option D is correct.
The answer is the bottom left one :D