Problem Solving

Please house, I need help with the following problems.

1. Before being simplified, the instructions for computing income tax in country R were to add 2 percent of one's annual income to the average (Arithmetic mean) of 100 units of country R's currency and 1 percent of one's annual income. Which of the following represents the simplified formula for computing the income tax, in country R's currency, for a person in that country whose annual income is I.
A. 50 + (I/200)
B. 50 + (3I/100)
C. 50 + (I/40)
D. 100 + (I/50)
E. 100 + (3I/100)

2. A committee of three people is to be chosen from four married couples. What is the number of different committees that can be chosen if two people who are married to each other cannot both serve on the committee?
A. 16
B. 24
C. 26
D. 30
E. 32

3. For each of her sales, a saleswoman receives a commission equal to 20 percent of the first $500 of the total amount of the sale, plus 30 percent of the total amount in excess of $500. If the total amount of one of her sales was $800, the saleswoman's commission was approximately what percent of the total amount of the sale?
A. 22%
B. 24%
C. 25%
D. 27%
E. 28%

4. When a certain tree was first planted, it was 4 feet tall, and the height of the tree increased by a constant amount each year for the next 6 years. At the end of the 6th year, the tree was 1/5 taller than it was at the end of the 4th year. By how many feet did the height of the tree increase each year?
A. 3/10
B. 2/5
C. ½
D. 2/3
E. 6/5

1)
LET INCOME BE I

EQN IS 2I/100+[(100+I/100)/2]

SOLVING 50+I/40

ITS C

2ND)
imo A

3RD)
ITS b

FOR $500 COMMISSION IS $100
FOR REST $300 COMMISION IS 30% OF 300=90
TOT=190

%=190/800 APPROX IS 24(23.7)

Q 4
imo 2/3 IE D

EQN IS 4+6R=6/5(4+4R)

SOLVING R=2/3

OA PLS

xcusemeplz2009 wrote:imo 2/3 IE D

EQN IS 4+6R=6/5(4+4R)

SOLVING R=2/3

OA PLS

Could you explain this equation ?

heshamelaziry wrote:

xcusemeplz2009 wrote:imo 2/3 IE D

EQN IS 4+6R=6/5(4+4R)

SOLVING R=2/3

OA PLS

Could you explain this equation ?

Q4

0 4
1 4+r
2 4+2r
3 4+3r
4 4+4r
5 4+5r
6 4+6r

relation given in q is that ht of 6th year is 1/5 taller than ht of 4th year ie is same as 6/5 of 4th year

from the above chart
4+6r=6/5(4+4r)
20+30r=24+24r
6r=4
hence r=4/6=2/3

xcusemeplz2009 wrote:2ND)
imo A

3RD)
ITS b

FOR $500 COMMISSION IS $100
FOR REST $300 COMMISION IS 30% OF 300=90
TOT=190

%=190/800 APPROX IS 24(23.7)

Please, I will like to know how to go about question 2 in the shortest possible time.

Tosino wrote:

xcusemeplz2009 wrote:2ND)
imo A

3RD)
ITS b

FOR $500 COMMISSION IS $100
FOR REST $300 COMMISION IS 30% OF 300=90
TOT=190

%=190/800 APPROX IS 24(23.7)

Please, I will like to know how to go about question 2 in the shortest possible time.

Question 2 was just discussed a couple of days ago.

https://www.beatthegmat.com/probability-t48205.html