幫幫手＊急×１００００００００

3:Peter goes swimming every 12 days .John goes swimming every 18 days.If the meet at swimming ppol or 3rd July ,when will they meet again at the pool?
*先計算12和18的公倍數*, 而應該計出36
再用3+36,就會知道答案是39,不過7月只有31,所以再把39-31,就會計出8th August了

4:The size of a stamp is 30mm×25mm.Find the minimum numbers of stamps that are required to make a sqare sheet stamps.
*如果要把stamps合為最細既正方形,即係每邊的長應該係30同25既倍數(150),再把150*150(最細既正方形面積)/750(一個stamp既面積),就知道答案係=30個stamps啦

2007-08-30 14:12:08 補充：
sorry,我忘記同你解題:3:Peter 每12天就去swim一次水,而John每18天先會swim一次,如果佢地7月3日係swimming pool見面一次,最快幾時先會再見?4:一張郵票既面積就係30mm*25mm.至少幾多張郵票先會合成一個正方形呀?

3. L.C.M of 12&18 = 36
Therefore they meet again after 36days,i.e. 8th August

4.Area=30x35=750mm2
750的最細倍數而可開方

答案係30個

Verify:
750x30=22500=150 o既二次