20. Given n ! = n ( n - 1 ) ( n - 2 ) ............ ´ 4 ´ 3 ´ 2 ´ 1

    \ ( n + 1 ) ! = ( n + 1 ) ( n ) ( n - 1 ) ( n - 2 ) ( n - 3 ) ..... ´ 3 ´ 2 ´ 1

    ( n - 1 ) ! = ( n - 1 ) ( n - 2 ) ( n - 3 ) ......... ´ 3 ´ 2 ´ 1

    From above

    ( n + 1 ) ! = ( n + 1 ) ( n ) ( n - 1 ) !       OR

          

    \ n ( n + 1 ) = 20

    But n and n + 1 are consecutive integers whose product is 20.

    Hence n = 4 and n + 1 = 5.

    Hence E

21. The area of the passage can best be worked out by subtracting the areas of both toilet and bathroom from the area between bedroom and kitchen.

    9 ´ 7 - ( 3 ´ 4 + 4 ´ 5 ) = 63 - ( 12 + 20 )

    = 63 - 32

    = 31 sq. ft.

    Hence C.

22. The kitchen area is 6’ ´ 9’ = 54 sq. ft.

    Whereas the bedroom area = 9’ ´ 9’ = 81 sq. ft.

    Hence the required fraction is

    Hence D.

23. Bedroom area = 9’ ´ 9’ = 81 sq. ft.

    Hall area = 16’ ´ 9’ = 10 sq. ft.

    Hence the required fraction is

    Hence C.

24. 

    Hence D.

     

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Index

Test 4
Section 1 : Verbal Section
Section 2 : Quantitative Section
Section 3 : Analytical Section
Section 4 : Quantitative Section
Section 5 : Verbal Section
Section 6 : Analytical Section
Section 7 : Analytical Section
Answer key to Test 4

PART I To The Students