0 hundreds<span> is equal to 9000. To find the number of 10's in 9000, simply divide them 9000/10 = 900. Comments; Report</span>
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: 15%
Step-by-step explanation:
The Percentage decrease will be:
= Decrease in weight / Old weight × 100
= (200 - 170) / 200 × 100
= 30/200 × 100
= 15%
The Percentage decrease is 15%
Remmeber you can do anything to an equaiton as long as you do it to btoh sides
5-6(a+2)=7+a
distribute
5-6a-12=7+a
add like terms
-6a-7=7+a
add 6a both sides
-7=7+7a
minus 7 both sides
-14=7a
divide by 7
-2=a
a=-2
