Ms. Evans

[prepgmat]

Please someone....

1. If Ms. Evans sold 1 acre more than 2/3 of her farm and had 4 acres less than 1/2 of it left, the number of acres in the original farm was?

a)11
b)13
c)18
d)21
e)30

2. Assuming that 2.54cm equal 1 inch, how many sixteenths of an inch (to the nearest sixteenth) equal 1 cm?

a)4
b)6
c)7
d)8
e)16

[Stuart@KaplanGMAT]

Please someone....

1. If Ms. Evans sold 1 acre more than 2/3 of her farm and had 4 acres less than 1/2 of it left, the number of acres in the original farm was?

a)11
b)13
c)18
d)21
e)30

Let's let the number of acres = x

x - ((2/3)x + 1) = (1/2)x - 4

x - (2/3)x - 1 = (1/2)x - 4

(1/3)x - (1/2)x = -4 + 1

-(1/6)x = -3

x = (-6)(-3)

x = 18

2. Assuming that 2.54cm equal 1 inch, how many sixteenths of an inch (to the nearest sixteenth) equal 1 cm?

a)4
b)6
c)7
d)8
e)16

1 inch = 2.54cm, so 1cm = 1/2.54 inches

We want to know how many 16ths of an inch = 1cm

So, x/16 = 1/2.54

At this point, we can either do the math or check the choices.

Algebra:

x = 16/2.54 = a bit less than 16/2.5 = 32/5 = 6.4 - round off to 6.

Backsolving from the choices:

Of the choices, 4 is too small (since 4/16 = 1/4) and 16 is too big (since 16/16 = 1), so we just need to try out the middle choice - if it's just right, then (c) is correct. If it's too big, choose (b), if it's too small, choose (d).

7/16 = just under .44
1/2.54 = just under .4 (we know this because 1/2.5 = 4/10 = .4)

So, 7/16 is too big, choose (b) 6

(for the record, 6/16 = 3/8 = .375)