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:
110.5 yd²
Step-by-step explanation:
Separate the figure into 1 triangle and 3 rectangles.
(see attached image)
<u>Area 1</u>
Area of a triangle = 1/2 × base × height
= 1/2 × (7 + 2 + 2) × 7
= 1/2 × 11 × 7
= 38.5 yd²
<u>Area 2</u>
Area of a rectangle = width × length
= 3 × (5 + 2 + 2)
= 3 × 9
= 27 yd²
<u>Area 3</u>
Area of a rectangle = width × length
= 5 × (5 + 2)
= 5 × 7
= 35 yd²
<u>Area 4</u>
Area of a rectangle = width × length
= 2 × 5
= 10 yd²
<u>Total Area</u>
Area 1 + Area 2 + Area 3 + Area 2 = 38.5 + 27 + 35 + 10
= 110.5 yd²
Answer:
x = 5
Step-by-step explanation:
im too tired to explain just trust me
(5) + 2 = 7
2(5) + 3 = 13
13 * 7 = 91
Charlie used a coupon and pos 9.99 for a pizza and it normally costs 15.99 14* the percentage of the change would be %1.28
The fraction of the total books about mammals is 7/18
Let the total number of books in the school be 1 whole , ie 12/12( since we are dealing with fractions)
Number of science books =7/12
Number of mammals books =2/3 of science books
=2/3 x 7/12=14/36 = 7/18
Since the total books are 12/12 which is also =1 whole
Then the fraction of total books that are about mammals are 7/18 x 1 whole =7/18
See related answer here: brainly.com/question/18443368
