It depends on the definition of day, solar day or stellar day.
Explanation: Solar day: 1 day = 24h
7 days = 168h
X=30 degrees for each of the congregant angles
Answer: 
Step-by-step explanation:
Given
Cost of white-washing =Rs. 4989.60
Rate =20 per meter square
So, inside area of = 
The surface area of dome= 
The volume of air in the dome 
SOLUTION:
As an equation it is:
y - 3x = 5y + 2x
If you are asking for it as a sentence ( I will do it as a written sentence as I unfortunately can't show you the sentence verbally as you had asked ), then it is as you had written in your question so:
Three times x less than y is five times y plus two times x
Or you could write is as:
y subtracted by three times x is equivalent to the sum of five times y and two times x.
Essentially, even with the small alterations that you can make to the phrasing and sentence structure, the concepts are the same so you can use one of the above answers or alter it as you please.
Hope this helps! :)
