Answer:
9/10
1/2+2/5
Since these fractions have different denominators, we need to find the least common multiple of the denominators.The least common multiple of 2 and 5 is 10, so we need to multiply to make each of the denominators = 10
1/2 ∗ 5/5 = 5/10
5/2∗ 2/2= 4/10
Since these fractions have the same denominator, we can just add the numerators
5/10+ 4/10 = 9/10
By scientific notation I am assuming you mean standard form, as that is used primarily in scientific calculations. The answer in standard form would be

I hope this helps!
Answer:
It will be worth 16k in 10 years
Step-by-step explanation:
divide 20k by 100
1% = 200 dollars
200 x 8 gives you 1.6k
1.6k x 10 = 16k
So if x is equal to 1/3, then our equation would be 5/(1/3). When dividing by a fraction, you can multiply by the reciprocal to find the answer, meaning that if you divide by 1/3, you can multiply by 3/1. So your answer would be 15.
5/(1/3)=x
5*3=x
15=x