the ratio of mary's age to alice's age is $3: 5$. alice is 30 years old. how many years old is mary?

Ten times the square of a non-zero number is eqaul to ninety times the number

Need plz been trying to do it for a long time and still haven’t succeeded

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?