Aptitude - Clock - Discussion

At first you multiple 1st hours by 5 (7*5=35),
Then you substitute 30 from the multiple values, (35-30=5),

That's the answer.
5* 5/11 [by rules of (x* x/11)].

That's answer will 7: 5* 5/11

@Vivek Jain.

In 1 hr minute, min hand covers 60 min and hr hand covers 5 min. Comparing both minute hand gains 55 min in 1 hr.

(210-6a)+(30/60)a = 180.

I think this will be the perfect solution.

At 7:05 both hands of the clock make a straight line.

So by taking 5 minutes use formula (5*12/11), that's it.

@Himanshu

How min hand increases angle? Please explain.

Between 7'c and 8'c not together. so its 180 degree.

55 = 60.
5 = x.
55x = 60 * 5.
55x = 300.
So, Answer = 5 5/11.

@Harshad

Man at 7 o clock, the hour hand is at 7 and the minute hand is in 12 i.e 60th min. assume the display in your watch is like 5 10 15.. 60.. so at 7 the hour hand will be at 35 and the min hand will be in 60.. now jus go on adding the minute space clockwise or els simple (60-35) gives 25 mins space..!!

ANOTHER METHOD:
In 7 o'clock there are angle between hands= 5*30=150 degree
we have to make that angle = 180 degree
let after X min
min hand will increase angle by = X*6 =6X,on 150 degree

1 degree of min = 1/12 degree of hr
6X degree of min = 6X/12 = X/2 degree of hr (decrease angle on 150)
so angle have to be between hands=180
150+6X-X/2=180
x=5+5/11
ANS=(5+5/11) minute and 7 past

@amit:11/2min-30h this formula applicable only when h<6
if u put h=6 or above then the min>60 which is not acceptable(for the 180 degree),
in this problem if we put that formula then the ans is 77(10/11)
but in that case the h=7 so we apply the another formula which is 30h-11/2
in this case if we put that then formula the ans is 5(5/11)
if u apply that formula then u will find that min<60 which is acceptable

BASICALLY WE NEED THIS 2 FORMULAS BUT IN DIFF CASE...
hope u will understand:)

What is the formula? whether its 11/2*min-30hr or 30hr-11/2*min?