Answer:
c=7
Step-by-step explanation:
The problem says that 8 less than 4 times c is less than twenty, so we can first show 8 less than 20.
4c -( I did this because it said 4 times the number c)
Then, we show 8 less than that.
4c-8
It says it is twenty, and that means it equals twenty.
4c-8=20
Now we solve!
4c-8=20
+8 +8
*we add 8 to both sides*
4c=28
*we divide both sides by 4 since we want to isolate c*
c=28/4
c=7
I hope this helped!
First you have all ten books, but then every time after, you loose one because you can't put the same book in the group twice.
10 * 9 * 8 * 7 = 5040 groups
Answer:
249 cm^2
Step-by-step explanation:
This problem becomes easier if we subdivide the figure, find the areas of the resulting figures and then sum them up.
Draw a vertical line straight down from the edge marked "4 cm" towards the edge marked "18 cm." The resulting rectangle on the left is 15.5 cm long and (18 - 7.5) cm wide, or 15.5 by 10.5 cm. Its area is 162.75 cm^2.
Next, find the area of the rectangle on the right of the line we drew. Its width is 7.5 cm and its height (15.5 - 4) cm, resulting in an area of 86.25 cm^2.
Last, add together these two subareas: combine 86.25 cm^2 and 162.75 cm^2. The total area of the composite figure is then 249 cm^2 (answer).
