What did most ancient cultures primarily write out their mathematical texts in words?

Which is greater, 7 p 5 or 7 c 5? 7p5 7c5

Suppose y varies directly with x. write a direct variation equation that relates x and y. then find the value of y when x=12 y=7 when x=3

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document