1,2,3,4,5,6,7
1,2,3,4,5,6,7
how many pairs of different numbers can be chosen from the list above so that the sum of the two numbers is even?(note:the pair 1,3 is the same as the pair 3,1)
第二題
square tiles measuring 1/2 foot by 1/2 foot are sold in boxes containing 10 tiles each.what is the least number of the boxes of tiles needed to cover a rectangular floor that has dimensions 12 feet by 13 feet?
這道真心沒看懂= =
how many pairs of different numbers can be chosen from the list above so that the sum of the two numbers is even?(note:the pair 1,3 is the same as the pair 3,1)
第二題
square tiles measuring 1/2 foot by 1/2 foot are sold in boxes containing 10 tiles each.what is the least number of the boxes of tiles needed to cover a rectangular floor that has dimensions 12 feet by 13 feet?
這道真心沒看懂= =
英語(yǔ)人氣：225 ℃時(shí)間：2020-05-22 12:45:51
優(yōu)質(zhì)解答
1.Grp A (0dd numbers):1,3,5,7Grp B (Even numbers):2,4,6U can choose 2 both from Grp A or from Grp B,totally:C(2,4)+C(2,3)=92.12×13÷(1/2×1/2×10)=62.4≈63
我來(lái)回答
類似推薦
- 以前學(xué)過的知識(shí)都忘了
- SAT兩道數(shù)學(xué)題求解答!
- 急啊!sat 數(shù)學(xué)題求解
- At a bottling company,machine A fills a bottle with spring water and machine B accepts the bottle only if the number of
- sat OG的717頁(yè)section 4的第17題,關(guān)于3d figure的segment的那個(gè),這個(gè)題怎么翻譯/理解,那個(gè)答案是怎么出來(lái)的?
- 急!幫忙翻譯下列文字~
- 次氯酸不穩(wěn)定,見光易分解生成鹽酸并放出氧氣.寫出該反應(yīng)化學(xué)式
- 一輛汽車從甲地開往乙地,第1小時(shí)行了全程的25％,第2小時(shí)行了50千米,兩個(gè)小時(shí)一共行了全程的45％相距多
- are not的縮寫形式怎么寫?
- 已知函數(shù)fx=2cos(wx+π/4)(w>0)的圖像與函數(shù)gx=2sin(2x+α)+1的圖像的對(duì)稱軸完全相同.求fx單調(diào)遞增區(qū)間
- 其鄰人之父亦云的云今義是什么意思
- 導(dǎo)體為0.10mm的銅絲,請(qǐng)問截面積怎么算啊?公式是什么?
猜你喜歡
- 1（1）九分之二的分子加4,要使分?jǐn)?shù)大小不變,分母應(yīng)（）.
- 2They'll stay for five days in Harbin.（對(duì)劃線部分提問） ------------
- 3悲憫惻隱之心 義無(wú)反顧
- 4一道初中乘方題
- 5將下列句子中的直接引語(yǔ)變?yōu)殚g接引語(yǔ)
- 6it was frist time...that誰(shuí)能用這個(gè)句型造2個(gè)句子
- 7三角洲的形成有什么因素
- 81、He read the letter to all his friend【改被動(dòng)語(yǔ)態(tài)】
- 9在角ABC中,AB=AC AD垂直BC于D角ABC周長(zhǎng)的為36,角ABD的周長(zhǎng)為30.請(qǐng)你求出AD的長(zhǎng)
- 10一個(gè)數(shù)與4.85的和是14 1/2,求這個(gè)數(shù)《方程式》
- 11一項(xiàng)工程,甲,乙兩個(gè)工程隊(duì)合作,6天可以完工,現(xiàn)在甲先做4天,乙又接著做8天正好完工.乙每天完%B
- 12英語(yǔ)翻譯