<span>b^4 − b^3 + b − 1
=(</span><span>b^4 − b^3) + (b − 1)
= b^3(b - 1) + (b - 1)
=(b - 1)(b^3 + 1)</span>
Plan A costs a total of $95 since it says $95 for unlimited talk and text.
Plan B:
(.10 x 800) + (.05 x 1000)
The (.10 x 800) represents 10 cents per talk minute for 800 minutes.
The (.05 x 1000) represents 5 cents per text message for 1000 text messages.
Solve:
.10 x 800 = 80
.05 x 1000 = 50
80 + 50 = 130
This means Plan B will cost him $130 under these conditions.
Plan C:
20 + ((.05 x 800)+(.05 x 1000))
The 20 + represents a flat rate of $20 per month.
The (.05 x 800) represents 5 cents per call minute.
The (.05 x 1000) represents 5 cents per text.
Solve:
.05 x 800 = 40
.05 x 1000 = 50
20 + 40 + 50 = 110
This means Plan C will cost him $110 under these conditions.
Plan D:
45 + (.10(800 - 500))
The 45 + represents a flat monthly rate of $45.
The (800 - 500) represents how many minutes he has to pay for with the 500 free.
The .10 is the cost per extra minute.
Solve:
800 - 500 = 300
.10 x 300 = 30
45 + 30 = 75
This means Plan D will cost him $75 under these conditions.
In short:
Plan A- $95
Plan B- $130
Plan C- $110
Plan D- $75
The least expensive among these is Plan D, which only costs $75 per month.
Answer:
80m^3
Step-by-step explanation:
Here,
For the base of pyramid which is a rectangle,
length(a) = 8m
breadth(c) = 5m
For the pyramid,
actual height (h) = 6m
Now,
The formula for the Volume of a rectangular based pyramid is,
1/3 * Area of base rectangle * height
= 1/3 * (a*c) * 6 [ Because area of rectangle is product of its two sides, length and breadth]
= 2 * 8 * 5
80m^3