Aptitude Contest -118

[HELP]

1. It costs Rs. x each to make the first thousand copies of a compact
disc and Rs. y to make each subsequent copy. If z is greater than 1000,
how much will it cost to make z copies of the compact disc?




(a) zx - zy

(b) 1000x + yz

(c) 1000 (x - y) + yz

(d) 1000 .(z - y) + xz



2. Along a yard 225 metres long, 26 trees are planted at equal
distances, one tree being at each end of the yard. What is the distance
between two consecutive trees?



(a) 8 metres

(b) 9 metres

(c) 10 metres

(d) 15 metres



3. A boy was asked to multiply a number by 25. He instead multiplied
the number by 52 and got the answer 324 more than the
correct answer. The number to be multiplied was:



(a) 12

(b) 15

(c) 25

(d) 32





4. In how many different ways can the letters of the word 'MATHEMATICS' be arrange: so that the vowels always come together?



(a) 10080

(b) 4989600

(c) 120960

(d) None of these



5. In how many different ways can the letters of the word 'MACHINE' be
arranged. 'mat the vowels may occupy only the odd positions?



(a) 210

(b) 576

(c) 144

(d) 1728

(e) 3456

[WISDOM]

1.cost = 1000 x + (z-1000)*y = (c)

2.225/25 = 9 m

3. x*27 = 324 => x = 12

4. 8! * 4! / (2! * 2! * 2!) = 720 * 7 *24 = 120960

5. my answer is 144 (not very sure )

Edited by: WISDOM

[shreenath]

wisdom thanx for ur answers but plz explain 2nd one as its ? 225/26 or 225/25.

[sreepriyareddy]

hi

in 2nd problem

1st tree has to be neglected because after 1st tree we'll calculate the distance,i.e b/w 1st and 2nd tree ....

so we'll get 25 instead of 26

[sreepriyareddy]

hi

can anyone explain the 5th problem?

[WISDOM]

Originally Posted by shreenath

wisdom thanx for ur answers but plz explain 2nd one as its ? 225/26 or 225/25.

hey shreenath(Javagal?),

b/w 2 trees, space = 1

b/w 3 trees, spaces = 2 and so on

c fig. below

|........|; |...............|................| ; |........|............|...........|

b/w 26 trees, spaces = 25; since all these are equl so 25x = 225 => x=9[img]smileys/smiley2.gif[/img]

[WISDOM]

Originally Posted by sreepriyareddy

hi

can anyone explain the 5th problem?

u need to hv lil' knowledge of prbability to solve it. i solved it in haste and got the above mentioned answer. the procedure is u select any 3 odd nos. out of4(1,3,5,7) and at these positons u can put the vowels. further, u can arrange them in 3!ways; so 4c3 * 3! = 24

now put rest of the nos in the rest 4 spaces and arrange them in 4! ways

u get 24 * 24 = 576!!!!!!!!!!!!!!!!!!!!!! [img]smileys/smiley36.gif[/img][img]smileys/smiley36.gif[/img] [img]smileys/smiley36.gif[/img][img]smileys/smiley36.gif[/img]

which one is right??? it seems to be correct; well, i must have messed up somewhere. anyway, the logic is correct[img]smileys/smiley9.gif[/img]