Official Quant thread for CAT 2013

rachit_28 · November 16, 2012, 4:14pm

@Brooklyn said:
a

please explain.

@rkshtsurana @gs4890

angel.mehra · November 16, 2012, 4:15pm

@gs4890 said:
Q.4

i think

ans is [-7,2) u (2,3)

soham2208 · November 16, 2012, 4:15pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all theoptions which can give the length of the base.A. 4 cm B. 6 cm C. 8 cm D. 9 cm

B and C

realslimshady · November 16, 2012, 4:16pm

N=(2^15)*(3^12)

how many factors of n^2 are less than n but do not divide n completely

a.387

b.180

c.208

d.310

gs4890 · November 16, 2012, 4:16pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all theoptions which can give the length of the base.A. 4 cm B. 6 cm C. 8 cm D. 9 cm

6&8 ?

rkshtsurana · November 16, 2012, 4:17pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all theoptions which can give the length of the base.A. 4 cm B. 6 cm C. 8 cm D. 9 cm

6 and 8

gs4890 · November 16, 2012, 4:18pm

@realslimshady said:
N=(2^15)*(3^12) how many factors of n^2 are less than n but do not divide n completely a.387 b.180 c.208 d.310

180 ?

brooklyn · November 16, 2012, 4:19pm

@gs4890 said:
6&8 ?

@rkshtsurana said:
6 and 8

post approach too 😃

torque024 · November 16, 2012, 4:20pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all theoptions which can give the length of the base.A. 4 cm B. 6 cm C. 8 cm D. 9 cm

6,8

saurav5517 · November 16, 2012, 4:20pm

@realslimshady said:

N=(2^15)*(3^12)

how many factors of n^2 are less than n but do not divide n completely

a.387

b.180

c.208

d.310

c. 208??

rachit_28 · November 16, 2012, 4:21pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all theoptions which can give the length of the base.A. 4 cm B. 6 cm C. 8 cm D. 9 cm

B and C

gs4890 · November 16, 2012, 4:21pm

@Brooklyn said:
post approach too

area of iscosceles triangle

b/4 _/4a^2 - b^2

thus, b/4 _/100 - b^2

now only 6 & 8 gives u 12

soumitrabengeri · November 16, 2012, 4:22pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all theoptions which can give the length of the base.A. 4 cm B. 6 cm C. 8 cm D. 9 cm

b/4*root(4*a^2 - b^2 ) =12

where a is one of the 2 equal sides and b is the non equal sides..

Both 6 and 8 can be the possible values for the equation

saurav5517 · November 16, 2012, 4:23pm

@Brooklyn said:
The area of an isosceles triangle is 12 sq. cm. If one of the equal sides is 5 cm long, mark all the
options which can give the length of the base.
A. 4 cm B. 6 cm C. 8 cm D. 9 cm

B and C?

ashmukh · November 16, 2012, 4:23pm

@rkshtsurana solve kaise kiya??

brooklyn · November 16, 2012, 4:24pm

The square root of the harmonic mean of the roots of the equation
(5 + rt(2) )x2 − (4 + rt(5) )x + 8 + 2rt(5) = 0 is.

A. ± 3 B. ± 4 C. 2 D. None of these

Post approach for others :)

nihilist1002 · November 16, 2012, 4:24pm

@Brooklyn 6n8

assume other side to be 2a

and then apply sqrt(s(s-a)(s-b)(s-c))

gs4890 · November 16, 2012, 4:24pm

@saurav5517 said:
c. 208??

iska seedha formula hain

=> (total no. of factors of n^2 + 1) / 2 - total no. of factors of n

so, 180 aaega

saurav5517 · November 16, 2012, 4:26pm

@Brooklyn said:
The square root of the harmonic mean of the roots of the equation
(5 + rt(2) )x2 − (4 + rt(5) )x + 8 + 2rt(5) = 0 is.

A. ± 3 B. ± 4 C. 2 D. None of these

Post approach for others

C. 2?

brooklyn · November 16, 2012, 4:27pm

@saurav5517 said:
C. 2?

logic too plz 😃