if y=5x^3/z ,what happens to the value of y when both x and z are doubled?
(A)y is not changed
(B)y is halved
(C)y is doubled
(D)y is tripled
(E)y is multiplied by 4
5.101001000100001......
the decimal number above consists of only 1's and 0's
to the right of the decimal point. the first 1 is followed by one 0,
the thrid 1 is followed by three 0's, and so on
what is the total number of 0's between the 98th and the 101st
1 in this decimal?
math problem!!
2006-10-23 7:17 am
回答 (2)
2006-10-23 8:01 am
✔ 最佳答案
y=5x^3/z當 x double, 因為 x^3 既原故, 所以變大左 8倍
但係當 z double, 就會抵消左2倍
所以最後係E
1st 1 後面有1個 0
2nd 1 後面有2個 0
所以,
98th 1 後面有98個 0
99th 1 後面有99個 0
100th 1 後面有100個 0
total number of 0 is:
98 + 99 + 100
= 297
2006-10-23 8:04 am
first question
y=5x^3/z
after x and z are doubled,
new y = 5(2x)^3/(2z)
= 20x^3/z
= 4 x (5x^3/z)
= 4 x y
so, new y is y mulitplied by 4
the answer is (E)
second question,
what is the meaning of 1' and 0'?
i don't quiet understand your question, sorry
y=5x^3/z
after x and z are doubled,
new y = 5(2x)^3/(2z)
= 20x^3/z
= 4 x (5x^3/z)
= 4 x y
so, new y is y mulitplied by 4
the answer is (E)
second question,
what is the meaning of 1' and 0'?
i don't quiet understand your question, sorry
參考: from my calculation
收錄日期: 2021-04-23 19:49:17
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