Hey guys i'm in a bit of trouble considering i have just entered the wrong exam and if i leave the page i will not be able to access it again, so considering my situation will anyone be willing to me with the questions below?

Abari owns 100 shares of stock a and 45 shares of stock b. for the past month, his stocks have been fluctuating inversely. stock a decreased by m cents per share and stock b increased by n cents per share. which equation can be used to find the total change in value of jabari's shares per month?