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.
1 ft = 12 inches
(1 ft)^3 = (12 inches)^3
1 cubic foot = 1728 cubic inches
You'll multiply by the conversion factor (1278 in^3)/(1 ft^3) to convert from cubic feet to cubic inches. Notice how the cubic feet ft^3 unit is at the bottom of the conversion fraction, so that the cubic feet units cancel.
Answer: A) multiply by 1728
Answer: 2x^2-7x-15
Step-by-step explanation:
reorder the terms (x*2+3)*(x-5)
multiply the parentheses
(2x+3)*(x-5)
collect like terms (2x^2-10x+3x-15)
product= 2x^2-7x-15
<h3><u>
Answer:</u></h3>
<h3><u>
Step-by-step explanation:</u></h3>
<em>There can be many ways to find the number.</em><em> I have found the number with the help of fractions and multiplication. </em><em>Below is the solution to your problem.</em>
- 80 = 20/100
- => 5 x 80 = 20 x 5/100
- => 400
<h3><u>
Conclusion:</u></h3>
<em>Hence, 80 is 20% of 400. </em><em>I hope my method helped you.</em>

Answer:
the first one
Step-by-step explanation:
The correct one is the one in the top left corner.
A great website to find out things like this is
https://www.mathpapa.com/algebra-calculator.html