Lona read 40 books for the read-a-thon. she read 30% historical fiction and20% sports stories. the rest were mysteries. how many mysteries did lona read?

20 mysteries. Add 20% and 30% to get 50%. Then rewrite 50% as 50/100. Next multiply 50/100 by 40 to get 2,000/100.The last thing to do is simplify to get 20 and subtract 20 from 40 to get 20 mysteries.

step-by-step explanation:

let's assume

number of candles set =x

price of of x candles =p(x)

we are given

a candle maker prices one set of scented candles at $10 and sells an average of 200 sets each week

so, we get point as (200,10)

he finds that when he reduces the price by $1, he then sells 50 more candle sets each week

so, we can find slope

now, we can use point slope form of line

now, we can plug values

we can use point

and find b

now, we can plug it back

and we get

now, we can find revenue

we know that

revenue = price*quantity

so, we get