Quantitative Aptitude - Arithmetic Ability Questions

The sum of the digits in 708, 618 and 816 is 15, but not in 392.

As given equal amounts of alloys are melted, let it be 1 kg.

Required ratio of gold and silver = 513 + 58813 + 38 = 105103.

Hence, ratio of gold and silver in the resulting alloy = 105/103.

Let 138.009 + 341.981 - 146.305 = 123.6 + z

Then, z = (138.09+341.981) - (146.305+123.6)= 479.99 - 269.905 = 210.085

0.75 = 75/100 = 3/4

9th May, 2001 = (2000 years + Period from 1.1.2001 to 9.5.2001)

Odd days in 1600 years = 0

Odd days in 400 years = 0

Jan. Feb. March April May 

(31 + 28 + 31 + 30 + 9) = 129 days

129 days = (18 weeks + 3 day)= 3 odd day.

Total number of odd days = (0 + 0 + 3 ) = 3 odd day.

Given day is Wednesday.

Tota profit percentage = (119 x 100/85) - 100 = 3400/85 = 40% 

Let the speed of current = 'C' km/hr

Given the speed of boat in still water = 6 kmph

Let 'd' kms be the distance it covers.

According to the given data,

Boat takes thrice as much time in going the same distance against the current than going with the current

i.e, d8 - C = 3 × d8 + C

$$\begin{gathered} ⇒ 24 - 3C = 8 + C \\ ⇒ 4C = 16 \\ ⇒ C = 4 kmph \end{gathered}$$

Hence, the speed of the current C = 4 kmph.