Aplane flies from base camp to lake a, 200 km away in the direction 20.0° north of east. after dropping off supplies it flies to lake b, which is 230 km at 30.0° west of north from lake a. graphically determine the distance and direction from lake b to the base camp.

Distance of lake a is 200 km at 20 degree north of east

distance between lake a and b is 230 km at 30 degree west of north

now the distance between base and lake b is given as

given that

now the total distance is

now the magnitude of the distance is given as

also the direction is given as

so it is 277.4 km at 74.7 degree North of East

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form