請教我數學,有6題
唔該列詳細步驟,唔好跳步啊
1.the speed of train is deceased by r%. Find the percentage change
in the time taken to travel the same distance
answer: ( r÷(100-r) )%
2 A sum of $P is invested at r% p.a. , compounded yearly. after
2years ,the total interest is $ K. Find P
answer: 10000K÷(r(r+200))
3. Andy 's weight is measured to be 64kg and the percentage error
is 0.78125%. Which of the following cannot be his actual weight
answer: 64.53kg
4.if the percentage error in the length of a spuare is 1%, whist is the
percentage error in the area of the square
answer:2.01%
5. The measurement is correct to the nearest 0.1cm.The radius is 5.2cm
The height is 6.1cm. Find the greatest possible surface area of the cylinder.
answer:376 cm2
唔該哂啊~~