As a bicycle salesperson, Norman earns a fixed salary of $20 per week plus $6 per bicycle for the first six bicycles he sells, $12 per bicycle for the next six bicycles he sells, and $18 per bicycle for every bicycle sold after the first 12. This week, Norman earned more than twice as much as he did last week. If he sold x bicycles last week and y bicycles this week, which of the following statements must be true?
I. y > 2x
II. y > x
III. y > 3
I only
II only
I and II
II and III
I, II and III
I want to understand how to pick numbers for such questions?
Sales PS
This topic has expert replies
- ssmiles08
- Master | Next Rank: 500 Posts
- Posts: 472
- Joined: Sun Mar 29, 2009 6:54 pm
- Thanked: 56 times
I didn't pick numbers. Maybe some one can show how to pick numbers.
From this question stem itself you know that y > x b/c he must have sold greater number of vehicles this week for his revenue to be twice as great.
so (II) is true.
set up the equation. 20 + 6*6 + 12(y-6) + 18(y-12) = This week.
This week = 2*Last week; Last week = x, so this week is 2x
20 + 6*6 + 12(y-6) + 18(y-12) = 2x.
20 + 36 + 12y - 72 + 18y - 216 = 2x.
30y - 232 = 2x
x = 15y - 106.
from the above equation, you can find out that he at least sold 8 more bicycles this week than last week b/c if he sold 7 more, you would get a negative value for x and that is not possible.
(-1) = 15*7 - 106.
14 = 15*8 - 106
Now we know the least amount of vehicles he sold was definitely y > 3
so (III) is also true.
(I) doesn't always have to be true. He makes twice as much not sells twice as much.
IMO D.
From this question stem itself you know that y > x b/c he must have sold greater number of vehicles this week for his revenue to be twice as great.
so (II) is true.
set up the equation. 20 + 6*6 + 12(y-6) + 18(y-12) = This week.
This week = 2*Last week; Last week = x, so this week is 2x
20 + 6*6 + 12(y-6) + 18(y-12) = 2x.
20 + 36 + 12y - 72 + 18y - 216 = 2x.
30y - 232 = 2x
x = 15y - 106.
from the above equation, you can find out that he at least sold 8 more bicycles this week than last week b/c if he sold 7 more, you would get a negative value for x and that is not possible.
(-1) = 15*7 - 106.
14 = 15*8 - 106
Now we know the least amount of vehicles he sold was definitely y > 3
so (III) is also true.
(I) doesn't always have to be true. He makes twice as much not sells twice as much.
IMO D.
You got a dream... You gotta protect it. People can't do somethin' themselves, they wanna tell you you can't do it. If you want somethin', go get it. Period.
-
- Newbie | Next Rank: 10 Posts
- Posts: 8
- Joined: Sat Mar 07, 2009 6:21 pm
- Thanked: 1 times
Its D
You can be easily folled by forgetting about the $20/wk,
If you forgot about that, then A would be true.
As x(2) = 1bike for x = $6.00
Y being 3 , 3(6)=$18
But with the $20/wk
Its $26 and $38
Don't forget to translate X bikes x 6.
B: There is no way y can be smaller than X.
C. Y has to be atleast 4 to get over the half way hump even if X sells 0 bikes the week before.
X = 0 = $20
Y = 4 X 6 = $24.00 + 20 = $44.00
You can be easily folled by forgetting about the $20/wk,
If you forgot about that, then A would be true.
As x(2) = 1bike for x = $6.00
Y being 3 , 3(6)=$18
But with the $20/wk
Its $26 and $38
Don't forget to translate X bikes x 6.
B: There is no way y can be smaller than X.
C. Y has to be atleast 4 to get over the half way hump even if X sells 0 bikes the week before.
X = 0 = $20
Y = 4 X 6 = $24.00 + 20 = $44.00