1. The cost of a washing price of the washing machine is $500. The seller wants to make a profit of 55%.
(a) Find the marked price of the washing machine.
(b) The marked price of the washing machine is too high, so the seller offers a
discount of 30%. The seller thinks that he can make at least 10% of profit when
the washing machine is sold with the discount. Do you agree? Expain your
answer.
2. A right-angled triangle ABC with AB =8 cm, BC = 10 cm and AC = 6cm.
A solid is formed by rotating triangle ABC about AB.
(我不明白"A solid is formed by rotating triangle ABC about AB. " 的意思，所以不識做)
(a) Describe the solid formed.
(b) Find the total surface area of the solid formed in terms of π.
3. The graph of y=f(x)= 3^x intersects the straight line L: y=k on the x-axis.
如果有一條叫你 write down the domain of the graph of y=3^x，是什麼意思。
math's Q (help.............)
2013-12-15 11:21 pm
回答 (3)
2013-12-18 3:17 am
✔ 最佳答案
1a) marked price: 500 x (1+55%) = $7751b) New marked price after the discount: 775 x (1-30%) = $542.5
Marked price when 10% profit need to made: 500 x (1+10%) = $550
So, he cannot make at least 10% of profit when the washing machine is sold
with the discount.
2a) A solid is formed by rotating triangle ABC about AB means
a cone is form
2b) π(8)^2 + π (8) (10) = 144 π
3a) all real number
參考: myself
2013-12-16 1:02 am
Q2, 一個三角形, 你想像是一張三角形的咭紙, 然後你把一枝竹籤固定在AB, 你然後搓這竹籤把咭紙轉動,你會見到一個陀螺形的立體會轉出來, 這個立體就好像是兩個上下倒轉的圓錐體 (cones)
Q3, domain of the graph of y=3^x is the whole real line, for x being any real number. 即是問什麼 x 可以使 y 計出有意義的值。
Q3, domain of the graph of y=3^x is the whole real line, for x being any real number. 即是問什麼 x 可以使 y 計出有意義的值。
2013-12-16 12:02 am
I just answer u the first question:)
The marked price
(a)=500(1+0.55)
=775
(b)If he wants to make at least 10% of the profits,then the profit should be
=500(1+0.1)
=550
However,
after offering the discount ,the selling price will be
775(1-0.3)
=542.5
542.5<550
it's not possible
2013-12-15 16:02:27 補充：
any questions welcome e me !!!
The marked price
(a)=500(1+0.55)
=775
(b)If he wants to make at least 10% of the profits,then the profit should be
=500(1+0.1)
=550
However,
after offering the discount ,the selling price will be
775(1-0.3)
=542.5
542.5<550
it's not possible
2013-12-15 16:02:27 補充：
any questions welcome e me !!!
收錄日期: 2021-04-13 19:51:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20131215000051KK00101