Questions without an upvoted answer in Quantitative Aptitude

If $20$ wave crests pass a fixed point in an interval of $5$ minutes, then the frequency of the wave (in Hertz) is $\_\_\_\_$. (rounded off to three decimal places)

A radioactive isotope sample has a decay constant $\lambda= 2.31 \times 10^{-4} \text{year}^{-1}$. Initially the sample contains $8000 \times 10^{15}$ atoms. The sample d...

​​​An electricity utility company charges ₹$7$ per kWh (kilo watt-hour). If a $40$ -watt desk light is left on for $10$ hours each night for $180$ days, what would be the...

​​​A bag contains Violet (V), Yellow (Y), Red (R), and Green (G) balls. On counting them, the following results are obtained:The sum of Yellow balls and twice the number ...

A business person buys potatoes of two different varieties $\text{P}$ and $\text{Q}$, mixes them in a certain ratio and sells them at ₹ $192$ per kg.The cost of the varie...

A tank of $4 \: \mathrm{~m}^{3}$ contains an ideal gas mixture of $60 \%$ hydrogen and $40 \%$ nitrogen by volume at $100 \: \mathrm{kPa}$ and $300 \: \mathrm{K}$. Nitrog...

In an engineering college of $10,000$ students, $1,500$ like neither their core branches nor other branches. The number of students who like their core branches is $1 / 4...

For positive non-zero real variables $x$ and $y$, if\[\ln \left(\frac{x+y}{2}\right)=\frac{1}{2}[\ln (x)+\ln (y)]\]then, the value of $\frac{x}{y}+\frac{y}{x}$ is$1$$1 / ...

A person sold two different items at the same price. He made $10 \%$ profit in one item, and $10 \%$ loss in the other item. In selling these two items, the person made a...

A 'frabjous' number is defined as a $3$ digit number with all digits odd, and no two adjacent digits being the same. For example, $137$ is a frabjous number, while $133$ ...

Ankita has to climb 5 stairs starting at the ground, while respecting the following rules:1. At any stage, Ankita can move either one or two stairs up.2. At any stage, An...

$x: y: z=\frac{1}{2}: \frac{1}{3}: \frac{1}{4}$.What is the value of $\frac{x+z-y}{y}$ ?$0.75$$1.25$$2.25$$3.25$

In a partnership business the monthly investment by three friends for the first six months is in the ratio $3: 4: 5$. After six months, they had to increase their monthly...