Answer:
x = 50
Step-by-step explanation:
Answer:
The original number was 54.5.
Step-by-step explanation:
If a number is increased by 2.8%, then it is 102.8% of it's original number.
In mathematics, "of" in virtually all cases means "multiplied by".
Therefore, we do the opposite:
1. Convert to a decimal.
102.8% = 1.028
2. Divide by the decimal.

3. Round it to the nearest tenth.
54.47 rounds to 54.5.
Answer: 2/3 hours
Step-by-step explanation:
okay so the speed now is 850, which is 850/340 = 2.5 times the original speed
Since It's 2.5 times the original speed,
2.5x = 5/3
so x = 5/3/2.5 = 2/3
This one is best done by elimination:
We need to start 4 meters away, so B is clearly wrong.
We first move towards Mr. Wilson (i.e. distance is decreasing) so A is wrong.
Our speed is faster on the way back, so the two sloped section must have differing slopes, so D is wrong.
(D also doesn't start at 4, it's wrong for two reasons.)
Only C is left.
We can check each part to make sure. First we start at 4m, then move away, then stay still (zero slope) for three seconds, then move back faster (higher slope). All parts check out ok.