There's a lot of information given here, so let's eat slow here.
Joey scores a 40 at the end of his first year. That means that he's currently 20 years old (since given per instruction, after the first year one's grade is determined by doubling his/her age).
Now, come next year, or his second year at this psychology school, he's technically 21 years old. To find out the second year's grade, we want to double his age PLUS half of his previous grade.
Well, his second year is then going to be 21(2) + 20 = 62.
Now let's tackle the main question: what's his grade going to be the third year?
Well, he will be at an age of 22 on his third year at this school. Again, to find out his third year's grade, you're going to double his age (22x2), plus half of his previous year's grade (as calculated for his second year, his grade is 62; therefore, 62/2)
Having said that, the final answer would be 22(2) + 62/2 = 44 + 31 = 75 --> (D)
Thanks man! nice explanation gonna note that explanation into my collection.
Actually I am collecting questions posted here with 1 or 2 best explanations of them by members so that I can review them when practicing and also will share here as there is too much data but not compiled or organized. just my 2 cents. I am sure, others will compile too & then share them for community.
"Don't be afraid of the space between your dreams and reality. If you can dream it, you can make it so."