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:
47 rounds and Eve wins.
Step-by-step explanation:
If read right, the highest player, (player with the most tokens) has to lose 3 tokens each round, so starting off with Evelyn, 17 - 3 = 14, and the other two each have +1 added to them, so, E=14, A=17 V=16, now subtract three from A (Amelia) and don't forget that one token is always being discarded each round. So the toal number of tokens at the start was 48, (17 + 16 + 15) so right now the total tokens should be 47, which it is. now starting the second round, A gives up 3 tokens so, 17 -3, again equals 14 and each of the two other players get one token, so E=15, A=14 V=17. Now you know the general trend, so we can figure this out seeing that after each round the number of tokens decrease by one, so there will be a round till all tokens are out except one, so there will be 47 rounds and since E started with the highest number they will win.
Step-by-step explanation:
hope i helped pleae mark brainliest
A, C, And D
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(2.6 * 10^9) / (1.3 * 10^2) =
(2.6 / 1.3) * (10^9) / (10^2) =
2 * 10^7 or 20,000,000 <===