A) The first step needs 100 bricks, the second needs 98, the third needs 96, and so on. Therefore the number of bricks for the nth step is: a_n = a_1 + d(n-1), where a_1 = 100 (the first term), d = -2 (difference).
a_n = 100 - 2(n-1) = 102 - 2n, and for the 30th step, a_30 = 102 - 2*30 = 42. So the top step will need 42 bricks.
b) The total staircase will need: 100 + 98 + 96 + ... + 44 + 42, and there are n = 30 terms. Using the formula for the sum of an arithmetic sequence:
S = (a_1 + a_n)*n/2 = (100 + 42)*30/2 = 2130
Therefore, 2130 bricks are required to build the entire staircase.
Answer:
For the first one: they increase in by 14, so the three could be 73,87,101
Second: Sequential, increasing by 20, next could be 110, 130, 150
Third: Increase by 27, next three could be 122,149,176
In the given situation, the ratio of the perimeters of two rectangles is 4 to 7. The perimeter of the larger rectangle is 42 inches.Now, let's find the perimeter of the smaller.Let's solve for the answerRatio and formula:=> 4 : 7 = X = 42, where x is the unknown perimeter of the smaller rectangle=> 4 * 42 = 168 / 7 = 24Thus the answer is letter D. 24 inches is the parameter of smaller rectangle.<span>
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Answer:
The point is located at (0,7) is correct
The point is on the y-axis. is correct
Step-by-step explanation:
The point is located at (7,0). is wrong because first the x values comes and then y values come here the x value is 0 and y value is 7
The point is on the x-axis.this is also wrong as you can see that the point lies on y axis not x axis
