Quantitative Aptitude - Arithmetic Ability Questions

From the above formula i.e (m1 x t1/w1) = (m2 x t2/w2)

so, [(34 x 8 x 9)/(2/5)] = [(M x 6 x 9)/(3/5)]

so, M = 136 men

Number of men to be added to finish the work = 136-34 = 102 men.

First letter can be posted in 4 letter boxes in 4 ways. Similarly second letter can be posted in 4 letter boxes in 4 ways and so on.

Hence all the 5 letters can be posted in = 4 x 4 x 4 x 4 x 4 = 1024

By investing Rs. 1552, income = Rs. 128.

By investing Rs. 97, income =Rs.1281552×97= Rs. 8.

Dividend = 8%

We know that   Speed=distancetime 

distance= speed * time

⇒ d=40×518×9

   d= 100 mts.

LCM of (80, 85, 90) can be found by prime factorizing them.

80 → 2 × 2 × 2 × 2 × 5

85 → 17 × 5

90 → 2 × 3 × 3 × 5

L.C.M of (80,85,90) = 2 × 2 x 2 × 2 × 3 × 3 × 5 × 17

= 16 x 9 x 85

= 144 x 85

= 12240

L.C.M of (80,85,90) = 12240.

 Let sum be Rs.x then, S.I. =Rs. [ x * (27/2) * 4 * (1/100) ] = Rs. 27x/50 

Amount =Rs [ x + (27x/50)] = Rs.77x/50 

=> 77X/50 = 2502.50  

=>X= (2502.50 * 50)/77 = 1625 

Hence Sum = Rs.1625

If a number to be divisile by 88, it should be divisible by both "8" and "11"

Check for '8' :
For a number to be divisible by "8", the last 3-digit should be divisible by "8"
Here 72x23y --> last 3-digit is '23y'
So y=2 [ (i.e) 232 is absolutely divisible by "8"]

Chech for '11' :
For a number to be divisible by "11" , sum of odd digits - sum of even digits should be divisible by "11"
(7 + x + 3) - (2 + 2 + y)
(7 + x + 3) - (2 + 2 + 2)
(10 + x) - 6 should be divisible by "11"
for x = 7
=> 17 - 6 = 11 [ which is absolutely divisible by "11"]

So x = 7 , y= 2.

Quantity of fruit juice in the mixture = 70 - [70 x (10/100) ]= 63 litres.

After adding water, juice would form 87.5% of the mixture.

Hence, if quantity of mixture after adding x liters of water, [(87.5) /100 ]*x = 63 => x = 72 

Hence 72 - 70 = 2 litres of water must be added.