Explanation

Explanation

We are given:

x+y=10

xy=20

The sum of the reciprocals of the two numbers is: 1/x+1/y =x+y/xy

Substitute the given values:

=10/20

=1/2

Explanation

To solve this problem, you need to use the concept of profit percentage and the formula:

Profit = Selling Price - Cost Price

Given:

Selling Price = Rs. 118

Profit = 50% of Cost Price

Let's calculate the Cost Price:

Profit = (50/100) x Cost Price

Profit = Rs. 118 - Cost Price

Substitute the profit value:

(50/100) x Cost Price = Rs. 118 - Cost Price

Simplify and solve for Cost Price:

Cost Price = Rs. 78.66

Explanation

Find the equation of line I using the two-point form:

(y - 5) / (8 - 5) = (x - (-3)) / (6 - (-3))

(y - 5) / 3 = (x + 3) / 9

y = (1/3)x + 6

Check which point lies on line I:

(0, 6): 6 = (1/3)(0) + 6 => True

Answer: (0, 6)

Explanation

Explanation

Calculation:

Let, the present age of A = A

2 years ago, his age = A - 2

2 years from now, his age = A + 2

According to the question,

⇒  =  1/A - 2 + 1/A + 2 = 2/3

⇒ 3(A + 2 + A - 2) = 2(A + 2)(A - 2)

⇒ 6A = 2(A2 - 22)

⇒ A2 - 3A - 4 = 0

⇒ A2 + A - 4A - 4 = 0

⇒ A(A + 1) - 4(A + 1) = 0

⇒ (A - 4)(A + 1) = 0

⇒ A = 4 or -1

Since, age can't be negative A = 4

∴ The present age of A is 4 years.

Explanation

Principal amount (X) = 65800

Rate of interest (R) = 14% per annum

Time (T) = 4 years

Simple interest (SI) = (X x R x T) / 100

= (65800 x 14 x 4) / 100

= 36848

Total amount (A) = Principal + Simple interest

= X + SI

= 65800 + 36848

= 102648

So, Ali will indeed get a total amount of 102648 at the end of 4 years.

Explanation

Given that, P : Q = 8 : 15, Q : R = 3 : 2

P : Q : R = (8 x 3) : (15 x 3) : (15 x 2) = 24 : 45 : 30

∴ P : Q : R = 8 : 15 : 10

Here, consequent of first ratio should be equal to the antecedent of second ratio.

Explanation

Explanation

6 persons working 8 hours a day earn Rs. 8400 per week.

First, let's calculate the total hours worked by 6 persons in a week:

6 persons x 8 hours/day x 7 days/week = 336 hours/week

Now, let's calculate the total amount earned per hour:

Rs. 8400 per week ÷ 336 hours/week = Rs. 25 per hour

Now, let's calculate the total hours worked by 9 persons in a week:

9 persons x 6 hours/day x 7 days/week = 378 hours/week

Finally, let's calculate the total amount earned by 9 persons in a week:

378 hours/week x Rs. 25 per hour = Rs. 9450 per week

So, the correct answer is: Rs. 9450