5 is A, because it's the only number that is whole when square rooted.
6 is confusing because it only gives you one number per answer, unless you are to add the two distances together? Then it would be 7 because X's distance is +4 and Y's distance is +3
I do not have an answer for 7
8 is 3.7 (or C)
9 is an easy one. Find out what the L and W is, and since it's a square we only need to find one of them. We square root the area and we are given 14.96662955, if rounded we get 15. So the answer is A
10 I don't understand the "estimate" for a square root number, I was not taught that.
Answer: Sal used a debit card and paid a total of $324.80 for the stereo. (I took the test too)
Step-by-step explanation: Multiply $21.30 by 18 months. Then subtract the interest, $58.60, from the product because Sal paid immediately with a card which implies using a debit card. You get $324.80.
A hockey puck is sliding on frictionless ice on an infinite hockey rink.
Its speed is 36 km/hour. How far does the puck slide in 10 seconds ?
(36 km/hr) x (1,000 m/km) x (1 hr/3600 sec) x (10sec) =
(36 x 1,000 x 10 / 3,600) meters = <em>100 meters</em>
What is the puck's speed in miles per hour ?
(36 km/hr) x (0.6214 mi/km) = <em>22.37 mi/hr</em>
Answer:
2,674.14 g
Step-by-step explanation:
Recall that the formula for radioactive decay is
N = N₀ e^(-λt)
where,
N is the amount left at time t
N₀ is the initial amount when t=0, (given as 42,784 g)
λ = coefficient of radioactive decay
= 0.693 ÷ Half Life
= 0.693 ÷ 18
= 0.0385
t = time elapsed (given as 72 years)
e = exponential constant ( approx 2.7183)
If we substitute these into our equation:
N = N₀ e^(-λt)
= (42,787) (2.7183)^[(-0.0385)(72)]
= (42,787) (2.7183)^(-2.7726)
= (42,787) (0.0625)
= 2,674.14 g
The last one if I'm not mistaking
