ACT Fibernet announced the launch of 1Gbps (gigabits per second) wired broadband internet services in Hyderabad. It makes the `City of Pearls’ India’s first `Giga City.’ In Hyderabad, the 1 Gb plan will offer at Rs 5,999 per month.

We know that zero can't be in hundreds place. But let's assume that our number could start with zero.

The formula to find sum of all numbers in a permutation is

111 x no of ways numbers can be formed for a number at given position x sum of all given digits

No of 1 s depends on number of digits

So,the answer us

111 x 20 x (0+1+2+3+4+5) = 33300

We got 20 as follows. If we have 0 in units place we can form a number in 4*5 ways. This is for all numbers. So we have substituted 20 in formula.

Now, this is not the final answer because we have included 0 in hundreds place. so we have to remove the sum of all numbers that starts with 0.

This is nothing but the sum of all 2 digits numbers formed by 1 2 3 4 5. Because 0 at first place makes it a 2 digit number.

So the sum for this is 11 x 4 x (1+2+3+4+5).
=660

Hope u understood why we use 4. Each number can be formed in 4x1 ways

So, the final answer is 33300-660 = 32640

Out of 4 fruits, any 3 are chosen by 4 families.So the combinations are
Apple - A Cherries - C Banana - B Grapes - G
1) ACB
2) ACG
3) BCG
4) GAB

By 2nd condition, Miller family uses either i)ACB or ii)ACG
Now we have Robin, Mandy and Miller who uses apples (ACB,ACG,GAB)
while Miller and Mandy both uses A and C. That leaves GAB for Robin.

By 3rd condition Flure uses either C or G. So if we leave out the terms containing both C and G, we are left with ACB and GAB

Now, for the time being let's suppose Robin is not a Flure.
So ACB is taken by Flure.

So ACG has to be Miller and that leaves BCG to be Clark. So we get Robin - Jacob(GAB).

By 4th and 2nd conditions Erica and Mandy belong to the first two. That leaves Stacy - Clark(BCG).

By 2nd condition Mandy is not a Miller, so we get Mandy - Flure(ACB) and that leaves Erica - Miller(ACG).

Let the principle be Rs. P
As the amount double itself the interest is Rs. P too
So P = P x r x 15/100
=> r = 100/15 = 20/3 % = 6.66 %.

7 boxes & 24 Balls.
Let, n = No. of boxes ; m = No. of fruits
3n+3 = m---------->(1)
4(n-1)= m---------->(2)
=>4n-4 = 3n+3;
=>4n-3n = 4+3
n = 7
Put n=7 in eqn(1)
=> 3(7)+3 = m
21+3 = m
m = 24;

Number of boxes = 7 and fruits = 24