In a psychology school the grade of the students is determined by the following method: At the end of the first year the grade equals to twice the age of the student. From then on, the grade is determined by twice the age of the student plus half of his grade from the previous year. If Joey's grade at the end of the first year is 40, what will be his grade at the end of the third year?

75.
22*2 + (62/2) = 75.
11 years agoHelpfull: Yes(7) No(0)
let at end of 1st yr age = a
1st yr end grade= 2a
2nd " = 2(a+1)+ a=3a+2
3rd " = 2(a+2)+ (3a+2)/2= 2a+ 1.5a +4+1=75(a=20,from 2a=40)
ans=75
11 years agoHelpfull: Yes(3) No(0)
ANSWER;75
FIRST YEAR GRADE 40;age 20
sec year g=2*20+(40/2)=50
thi yearg=50+25=75
11 years agoHelpfull: Yes(3) No(1)
ans is 70.
11 years agoHelpfull: Yes(2) No(7)
75...
joeys grade at end f ist yr=20
joeys age during 1st yr=20
2nd year grade=21(2nd year age)*2+20(half 1st yr grade)=62
3rd year grade=22(3rd year age)*2+31(half 2nd year grade)=75
11 years agoHelpfull: Yes(2) No(0)
((20+1)2+40/2)/2+(22*2)=75
11 years agoHelpfull: Yes(1) No(0)
Grade at end of first year = 2*age= 2*20=40,
grade at end of second year= 2*(20+1)+(40/2)= 42+20=62,
grade at end of 3rd year=2*(21+2) + (62/2)= 75 Ans.
11 years agoHelpfull: Yes(0) No(0)
ans = 75
xplanation
at the end of 1st year=> grade = 2*age
grade = 40 (given) so age = 20 yrs
2nd yr
grade = 2* age + (grade of previous year/2)
so grade = 2*21 + (40/2)
grade of 2nd yr = 62
similarly, grade of 3rd yr = 2* age + (grade of previous yr /2)
= 2* 22 + (62/2)
= 44 + 31
= 75 ans
10 years agoHelpfull: Yes(0) No(0)
First year age is 20.......40 grade
second year age is 21....42+previous year grade half is 20 now grade is.......62
third year age is 22...44+previous year grade half is 31 now grade is .........75 final answer
9 years agoHelpfull: Yes(0) No(0)

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