GMAT Official Guide Quantitative Review 2019_ Book

PS05008

39. What is the perimeter, in meters, of a rectangular garden
    6 meters wide that has the same area as a rectangular
    playground 16 meters long and 12 meters wide?

(A) 48

(B) 56

(C) 60

(D) 76

(El 192

Geometry

Let L represent the length, in meters, of the

rectangular garden. It is given that the width of

the garden is 6 meters and the area of the

garden is the same as the area of a rectangular

playground that is 16 meters long and 12 meters

wide. It follows that 6L = (16)(12), and so

L = 32. The perimeter of the garden is, then,

2(32 + 6) = 2(38) = 76 meters.

1h e correct answer 1s D.

PS00918

40. 1 -0.000001 =

(A) (1.01)(0.99)

(B} (1.11)(0.99)

(Cl (1.001)(0.999)

(D) (1.111)(0.999)

(E) (1.0101)(0.0909)

Arithmetic -, ••• I

The task in this question is to find among the

available answers the expression that is equal to

(^1) - 0.000001 = 0.999999. In the case of option C,
the first of the two factors, (1.001), is equal to 1

• 0.001. One may therefore observe that (1.001)
  (0.999) = (1 + 0.001)(0.999) = 0.999 + 0.000999 =
  0 .999999. Option C is therefore a correct answer.
  For option A, (1.01)(0.99) = (1 + 0.01)(0.99) =
  0.9999. This option is therefore incorrect. For
  option B, (1.11)(0.99) = (1 + 0.1 + 0.01)(0.99) =
  0.99 + 0.099 + 0.0099 = 1.0989. This option is
  therefore incorrect. For option D, (1.111)(0.999) =
  0.999 + 0.0999 + 0.00999 + 0.000999 = 1.109889. I
  This option is therefore incorrect. For option E,
  (1.0101)(0.909) = 0.909 + 0.00909 + 0.0000909
  = 0.9181809. This option is therefore incorrect.
  1h e correct answer 1s C.

41. 
    

    4.5 bl飞r, ,.., v Answer Explanations
    PS04362
    1-41(1-20曰51) =
    (A) — 100
    (B) —60
    (C) 60
    (D) 75
    (E) 100
    Arithmetic
    1 -^41 (1- (^20) 1-1 51 ) = 4(20 - 5) = 4 X 15 = 60
    Th e correct answer 1s C.
    PS12934

    
    


42. 
    

    Of the total amount that Jill spent on a shopping trip,
    excluding taxes, she spent 50 percent on clothing, 20
    percent on food, and 30 percent on other items. If Jill
    paid a 4 percent tax on the clothing, no tax on the
    food, and an 8 percent tax on all other items, then the
    total tax that she paid was what percent of the total
    amount that she spent, excluding taxes?

    
    

(Al 2.8%

(Bl 3.6%

(Cl 4.4%

(D) 5.2%

(El 6.0%

Arithmetic

Let T represent the total amount Jill spent,

excluding taxes. Jill paid a 4% tax on the clothing

she bought, which accounted for 50% of the total

amount she spent, and so the tax she paid on the

clothing was (0.04)(0.ST).Jill paid an 8% tax on

the other items she bought, which accounted for

30% of the total amount she spent, and so the tax

she paid on the other items was

(0.08)(0.3T). Therefore, the total amount of

tax Jill paid was (0.04)(0.ST) + (0.08)(0.3T) =

0.02T+ 0.024T= 0.044T. The tax as a percent of

the total amount Jill spent, excluding taxes, was

(0,0;4T X 100)% = 4.4%.

The correct answer is C.