maths

1)157/(50*3.14)
=157/157
=1

2)15
BECAUSE佢地既最大公因數係15

1. first all of we have to find out how long can one wheel rotation runs,
circle perimeter is calculated as 2(pi)(r) or d(pi) (where r= radius, d=diameter, pi= pi, 3.14)
therefore one rotation = 0.5*3.14 (0.5=50cm, pi=3.14) = 1.57m
to go for a 157m, the wheel has to rotate=157/1.57=100 times

2. it is to find the HCF of 30 and 45

30=2*3*5
45=3*3*5

therefore the the length of the square is 3*5=15

單車車輪直徑長50厘米,走157米的路程,車輪要轉動多少次?
單車車輪直徑長50厘米,走15700厘米的路程,車輪要轉動多少次?
車輪要轉動:
15700/50(pi)
= 99.94930426
車輪要轉動100次


長方形木板30CM,闊45CM,把木板分割成面積最大的正方形,而正方形的邊長可整除木板的長和闊,正方形的邊長最長是多少?
找30和45的HCM
是15
因此正方形的邊長最長是15 cm

單車題: 把50x3.14/157=1
所以車輪只須轉動1次


轉動: 最大既正方形即係每邊都30cm啦
咁既話正方形的邊長最長30囉!!!!1
30/30=1 45/30=1.5 (唔知整除係咪即係冇餘數呀)

2007-03-13 21:57:32 補充：
不過上面個個好似岩d sorry呀