If a and b must be positive integers, what is the largest integer n such that 13a + 18b = n has no solutions?

You have a 32-foot fence around a square garden. there are 4 equal sections. you paint 13 of one section of the fence. what fraction of the fence did you paint? you have a 32-foot fence around a square garden. there are 4 equal sections. you paint 13 of one section of the fence. what fraction of the fence did you paint?

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists

Point r divides in the ratio 1 : 5. if the coordinates of e and f are (4, 8) and (11, 4), respectively, what are the coordinates of r to two decimal places?