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1.The total cost of a belt and a shirt is $112. The cost of the shirt is 3 times as much as that of the belt. Find the cost of the shirt.
2.If the sum of two consecutive odd numbers is 20, find the smaller number.
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1.The total cost of a belt and a shirt is $112. The cost of the shirt is 3 times as much as that of the belt. Find the cost of the shirt.
let $x be the cost of the belt

              x+3x = 112
                     x = cost of belt
therefore, 3x = cost of the shirt

2.If the sum of two consecutive odd numbers is 20, find the smaller number.
let x be the smaller number

x+(x+2) = 20
            x = smaller number  

點解15條係x+(+2)?(x+2)係點得來的?

x+3x=112
     4x=112
       x=28

x=The price of the belt
3x=The price of the shirt
第一題咁寫會清楚一點
我唔清楚你既格式係點
呢個比你參考

引用第2樓阿星於2008-10-14 21:12發表的  :
點解15條係x+(+2)?(x+2)係點得來的?

如果我說 x 是 1 (只是舉例任何一個單數)

1 的下一個單數便會是 1+2 即是 3

而不會是 x+1，因如 x 是單數，+1 便會變為雙數(even numbers)

因此便是， x (smaller)      +     x+2 (bigger)

引用第4樓bon1於2008-10-14 22:22發表的  :
如果我說 x 是 1 (只是舉例任何一個單數)
1 的下一個單數便會是 1+2 即是 3
.......

哦
我而家明哂啦
thx