223
-119
104
In stead of doing 3-9 and 2-1 do 23-19 then 2-1
Let's start by visualising this concept.
Number of grains on square:
1 2 4 8 16 ...
We can see that it starts to form a geometric sequence, with the common ratio being 2.
For the first question, we simply want the fifteenth term, so we just use the nth term geometric form:


Thus, there are 16, 384 grains on the fifteenth square.
The second question begs the same process, only this time, it's a summation. Using our sum to n terms of geometric sequence, we get:



Thus, there are 32, 767 total grains on the first 15 squares, and you should be able to work the rest from here.
Answer:
x = 20
Step-by-step explanation:
The angles shown are alternate exterior angles.
Alternate exterior angles are congruent
This means that 46 must equal 3x - 14
Note that we've just created an equation that we can use to solve for
We now use the equation to solve for x
3x - 14 = 46
add 14 to both sides
3x - 14 + 14 = 46 + 14
simplify
3x = 60
Divide both sides by 3
3x / 3 = x
60 / 3 = 20
We get that x = 20
Answer:
math error ...............
Answer:
Step-by-step explanation:
You can readily see from the diagram, above, that the side length of the middle cube will be between 3 and 4. You want to determine to the nearest hundredth what value between 3 and 4 represents the side length of the cube whose volume is 45 units^3.
Please note: the middle cube has been mislabeled. Instead of volume = 30 units^3, the volume should be 45 units^3.
Here's the procedure:
Guess an appropriate s value. Let's try s = side length = 3.5
Cube this: (3.5 units)^3 = 42.875. Too small. Choose a larger possible side length, such as 3.7: 3.7^3 = 50.653. Too large.
Try s = 3.6: 3.6^3 = 46.66. Too large.
Choose a smaller s, one between 3.5 and 3.6: 3.55^3 = 44.73. This is the best estimate yet for s. Continue this work just a little further. Try s = 3.57. Cube it. How close is the result to 45 cubic units?