The required expression is 100 - 0.2w
Step-by-step explanation:
Given,
Amount of radioactive substance = 100 mg
The substance decreases by 20% each week.
To find the remaining amount of the in w weeks.
Now,
Each week 20% = 0.2 of the substance will be decreased.
So, in w weeks 0.2×w of the the substance will be decreased.
Hence,
The remaining substance = 100 - 0.2w
Answer:
2 or less packs
Step-by-step explanation:
15.99 + 1.99g < 20.00 where g is the number of packs of gum
Subtract 15.99 from each side
15.99 + 1.99g - 15.99 < 20.00-15.99
1.99g < 4.01
Divide by 1.99
1.99g/1.99 < 4.01/1.99
g < 2.015075377
Harold must buy whole packs so g =2 or less
It is equal to 50% because you move the decimal places two times to the right. :)
The equation you would need to solve is <span><span>x^2</span>+(x+1<span>)^2</span>=421. I'm not at a college level though so i don't know how to.
Give me feedback if this helped!</span>
