Explanation

Explanation

Explanation

Let N of 1/12 = 3/48.

Then, N = 3/48 x 12 = 3/4

Explanation

Given:

a^2 + b^2 = 8 ... (Equation 1)

(a - b)^2 = 4

Expanding the left side of the equation: a^2 - 2ab + b^2 = 4

Now, substitute Equation 1 into this equation: 8 - 2ab = 4

Subtract 8 from both sides: -2ab = -4

Divide both sides by -2: ab = 2

So, the value of ab is 2.

Explanation

Explanation

To factorize the expression y^2 + y - 6, we need to find two numbers whose product is -6 and whose sum is 1 (the coefficient of the middle term).

These numbers are 3 and -2, so we can write:

y^2 + y - 6 = (y + 3)(y - 2)

Explanation

To evaluate this expression, we can simplify the fraction:

12.1 ÷ 19.8 = 0.61 (approximately)

11/18 = 0.61 (approximately)

Explanation

Explanation

The mixture contains 12% copper, which means that 12% of the mixture's weight is copper.

We want to find out how many kg of mixture is required to get 69 kg of copper.

Let's say the weight of the mixture is x kg.

Since 12% of the mixture is copper, the weight of copper in the mixture is 12% of x, which is 0.12x.

We are told that the weight of copper is 69 kg, so we can set up the equation:

0.12x = 69

To solve for x, we can divide both sides by 0.12:

x = 69 / 0.12

x = 575

So, the weight of the mixture is 575 kg.

Explanation

Let the total distance be x km.

The man covers half the distance at 6 km/hr, so the time taken to cover this half is:

Time = Distance / Speed = (x/2) / 6 = x/12

The man covers the remaining half at 3 km/hr, so the time taken to cover this half is:

Time = Distance / Speed = (x/2) / 3 = x/6

The total time taken to cover the entire distance is the sum of the times taken to cover each half:

Total Time = x/12 + x/6

To add these fractions, we need a common denominator, which is 12. So we can rewrite the fractions as:

Total Time = x/12 + 2x/12 = 3x/12 = x/4

Now, we can find the average speed:

Average Speed = Total Distance / Total Time = x / (x/4) = 4 km/hr

So, the correct answer is: 4 km/hr