Pretty simple question, but how the hell am I supposed to know whether to put an addition sign or a subtraction sign.

Ateam has p points. p = 3w + d w = wins d = draws a) a football team has 5 wins and 3 draws. how many points does the team have?

The half-life of a certain material is 0.004 second. approximately how much of a 20-gram sample will be left after 0.016 second? a. 5 grams b. 16 grams c. 0.32 gram d. 1.25 grams

You are living in aldine, tx and you are planning a trip to six flags in arlington, tx. you look on a map that has a scale of 0.5 inches to 30 miles. if the map shows the scale distance from aldine to arlington is 4 inches, how far is the actual distance?