Step-by-step explanation:
(4/3)–1 = 3/4 and (1/4)–1 = 4/1
now we have,
(3/4 - 4)–1 = (-13/4)–1
= -4/13
Answer:
x=30
Step-by-step explanation:
(3x-10)+(2x-20)=180// 5x-30=180//5x=150//x=30
Answer:
D. About 800 years
Step-by-step explanation:
Use the half-life equation:
A = A₀ (½)ⁿ
where A is the final amount,
A₀ is the initial amount,
and n is the number of half-lives.
0.90A₀ = A₀ (½)ⁿ
0.90 = (½)ⁿ
To solve for n, take log of both sides:
log 0.9 = n log 0.5
n = (log 0.9) / (log 0.5)
n = 0.152
It takes 0.152 half-lives. The half-life of carbon-14 is 5730 years.
0.152 × 5730 years = 871 years
The closest answer is D.
