Finding mole fraction from vapor pressure

Sat no calculator section question in the picture

Jim has found that he must consume 2,300 calories a day to reach his health goals, but he doesn't want to give up his afternoon snack of pretzels. unfortunately, he tends to eat the entire bag — which amounts to 1,300 calories! what strategy should jim use to improve his habits?

Given: m∠apc = 27°, m dc = 27° find: m ab