Mathematical way of figuring out how many friday the 13ths there are in a year

The scale for a map is 20 miles = 1/2 inch. the distance between two towns on the map is 3 3/4 inches. what is the actual distance between these towns? 150 miles 38 miles 75 miles 135 miles

What number should be added to the expression x^2+3x+ in order to create a perfect square trinomial? 3/2 3 9/4 9

Graph the line that represents a proportional relationship between d and t with the property that an increase of 33 units in t corresponds to an increase of 44 units in d. what is the unit rate of change of dd with respect to t? (that is, a change of 11 unit in t will correspond to a change of how many units in d? )