Hey! I stumbled upon this problem while practicing for the SAT. The boiling point of water at sea level is 212 degrees Fahrenheit. For every increase of 1,000 feet above sea level, the boiling point of water drops approximately 1.84 Fahrenheit. Which of the following equations gives the approximate boiling point B, in Fahrenheit, at h feet above sea level? A) B = 212 – 1.84h B) B = 212 – (0.00184)h C) B = 212h D) B = 1.84(212) – 1,000h Can you please help me? Thank you!

One way to make sure you get questions like these right is to plug in some values to see which equation makes sense. For example, you might choose to plug in 0 for h here because you know that at zero feet above sea level the boiling point should be 212° F. Choices C and D (more…)

Lisa gives her little brother Sam a 15-second (sec) head start in a 300-meter (m) race…

This no-calculator prompt is from the Daily Practice app:

Lisa gives her little brother Sam a 15-second (sec) head start in a 300-meter (m) race. During the race, Sam runs at an average speed of 5 m/sec and Lisa runs at an average speed of 8 m/sec, not including the head start.

Which of the following best approximates the number of seconds that had passed when Lisa caught up to Sam?

A. 5
B. 25
C. 40
D. 55