Answer:
3:2
Step-by-step explanation:
2 boys for every 3 girls
[[x]] means that the integer should be rounded down to the greatest integer that is of the same value as x or is lower than x.
Answer:
The answer is 6x+7x_4-20
Step-by-step explanation:
If the half-life is t, then every t days, the amount of the radioactive isotope will be cut in half.
(1/2)^(number of half-lives) = 3%
number of half-lives = ln(0.03) / ln(0.5)
This gives the number of half-lives as 5.06.
Then 300 days = (5.06)(length of 1 half-life)
length of 1 half-life = 300 / 5.06 = 59.29 days
Answer:
7. x = 3
Step-by-step explanation:
To find the value of x, use the triangle sum property. Every triangle has interior angles which add to 180 degrees. To solve, add the expressions and numbers together then set equal to 180. Then use inverse operations to solve for x.
7. 20x - 9 + 10x + 9 + 90 = 180 Subtract 90 from both sides.
20x - 9 + 10x + 9 = 90 Add -9 + 9 = 0
20x + 10x = 90 Add like terms 20x + 10x = 30x
30x = 90 Divide both sides by 30.
x = 3
Repeat this process for each problem.