In a certain year the price of gasoline rose by 20% during january, fell by 20% during february, rose by 25% in march, and fell by x% in april. the price of gasoline at the end of april was the same as it had been at the beginning of january. find the value of x.

Fell by 25%

Step-by-step explanation:

+20% January

-20% February (20-20 is zero, so we're back to the original price we started at here)

+25% March

?? April

Currently, we are 25% more than what we had, so to get back to normal, the price needs to go down by 25 percent. This will put us back to zero. Put another way...

+20%-20%+25%-25%=0% (Original Price)

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this

a is the right answer