A man is standing 20 feet away from the base of a VERY tall tree. He stands, 20 feet away from the tree, looking up at 35 degree angle to see the tip-top of the tree. He wants to know how tall that big tree is. How can he know?
For this question, I would draw a picture. Once you have a diagram with the tree and the man 20ft away at the base with 35 degree viewing angle, you have a better idea of what to do. Given that we have the given viewing angle of 35degrees and adjacent side of 20ft, we need to find the opposite side length in order to find the height of the tree. Which trig function uses adjacent and opposite? THAT'S RIGHT, TAN! We use TAN because TAN = opposite / adjacent. TAN (35) = X / 20 X = TAN(35) * 20 X = 14ft.
The molarity of an acidic solution is .0075, what is the pH?
To find the pH of a solution given the molarity of H+, you take negative log of [H+] to get pH. In this case, -log(.0075) = 2.12 pH = 2.12
You're sitting in your room when you hear the songs of the ice-cream truck. You can hear your tummy grumbling for an ice cream sandwich. You know your mom is going to say no when you ask so you need to find the money to pay for it. The ice-cream sandwich is going to cost you $3 from the ice-cream man. In your desk drawer you find 6 quarters, 3 dimes, 4 nickels and 8 pennies. How much more money do you need to find in order to buy the ice cream sandwich?
How much money do you have right now? 6 quarters = 6 * $0.25 = $1.50 3 dimes = 3 * $0.10 = $0.30 4 nickles = 4 * $0.05 = $0.020 8 pennies = 8 * $0.01 = $0.08 Add together to get total = $2.08 You need $3 to buy ice-cream, you have $2.08, how much more do you need? $3 - $2.08 = $0.92 You need $0.92! :)