Quantitative Aptitude - Arithmetic Ability Questions

Since the compound interest is taken here,

 PW1+51002=1764

=> PW = 1600

Let the number of boys = b

Let the number of girls = g

From the given data,

81b + 83g = 81.8(b + g)

81.8b - 81b = 83g - 81.8g

0.8b = 1.2g

b/g = 1.2/0.8 = 12/8 = 3/2

=> g : b = 2 : 3

Hence, ratio between the number of girls to the number of boys = 2 : 3.

t=I/pr

On 31st December, 2005 it was Saturday.

Number of Odd days from the year 2006 to the year 2009 = (1+1+2+1)=5 days.

 On 31st december 2009, It was Thursday

Thus, on 1st Jan, 2010 it is Friday.

Let the required height of the building be x meter

More shadow length, More height(direct proportion)

Hence we can write as

(shadow length) 40.25 : 28.75 :: 17.5 : x
⇒ 40.25 × x = 28.75 × 17.5
⇒ x = 28.75 × 17.5/40.25
= 2875 × 175/40250
= 2875 × 7/1610
= 2875/230
= 575/46
= 12.5 cm

We are not given a value of P in this problem, so either pick a value

for P and stick with that throughout the problem, or just let P = P.

We have that t = 1, and r = .055. To find the effective rate of interest,

first find out how much money we have after one year:

A = Pert

A = Pe(.055)(1)

A = 1.056541P.

Therefore, after 1 year, whatever the principal was, we now have 1.056541P.

Next, find out how much interest was earned, I, by subtracting the initial amount of money from the final amount:

I = A − P

  = 1.056541P − P

  = .056541P.

Finally, to find the effective rate of interest, use the simple interest formula, I = Prt. So,

I = Pr(1) = .056541P

.056541 = r.

Therefore, the effective rate of interest is 5.65%

From the given data,

K's profit : L's profit = 7x x 11 : 9x x 7

= 11:9

Therefore, L's profit = 9 x 2460/20 =  Rs. 1107