3)The original rational number was 17/12.
4)The age of Ruby and Reshma are 20 and 28 years respectively.
Explanation:
3)Let the numerator be x.
So denominator will be (x - 5)
If we add 5 to numberator then it will be (x + 5)
New number is (x + 5)/(x - 5)=11/6
Solve for X by cross multiplying
6(x + 5)=11(x - 5)
6x + 30=11x - 55
5x=85
x=17
So original rational number was 17/12.
4)The ages of Ruby and Reshma are in the ratio 5:7
So, let the present ages of Ruby and Reshma be 5x and 7x respectively.
Also, it is given that four years from now the ratio of their ages will be 3:4
So, the equation - 5x + 4 / 7x + 3 = 3/4
⇒4(5x+4)=3(7x+4)
⇒20x+16=21x+12
⇒21x−20x=16−12
⇒x=4
⇒5x=20 and 7x=28
The age of Ruby and Reshma are 20 and 28 years respectively.
To find the volume of a triangular pyramid, the formula is:

So we start by finding the area of the base, which is in the shape of a right triangle in this case.
The area of a right triangle is equal to 1/2 x base x height.

We use this area to find the volume.

The volume of the triangular pyramid is 30 cubic feet.
Congruent triangle are the same shape and same size exactly
The first one is (z-7)(z-1)
second: (x+1/3)(x+1/3)
third: (x-1/5)(x-1/5)
fourth: (x-5)(x-2)
Answer:
6.59999999999999999977 × 10^17
Step-by-step explanation:
6.6 x 10^17 - (9.2 x 10^14)/(4 x 10^16)