5 teeb meem olympiad hauv kev ua lej uas tsis yog txhua tus neeg laus tuaj yeem daws tau

2024 Tus sau: Malcolm Clapton | [email protected]. Kawg hloov kho: 2023-12-17 03:58

Sim daws cov dej num los ntawm lub tsev kawm ntawv kev sib tw-kev ua si "Kangaroo" yam tsis muaj kev tshoov siab.

1. Txog vases nrog txiv apples thiab txiv duaj

60 lub txiv apples thiab 60 txiv duaj tau muab tso rau hauv lub vases kom txhua lub vases muaj cov txiv apples sib npaug, tab sis ob lub vases muaj ntau tus txiv duaj. Dab tsi yog cov vases loj tshaj plaws uas tuaj yeem siv tau?

Nyob rau hauv tag nrho cov vases 60 txiv apples raug faib sib npaug. Qhov no txhais tau hais tias tus naj npawb ntawm vases yuav tsum raug xaiv los ntawm cov lej uas 60 yog faib tsis tau qhov seem.

Nws tseem paub tias txhua lub vase yuav tsum muaj tus lej sib txawv ntawm txiv duaj. Cia peb sim muab cov txiv hmab txiv ntoo tso rau hauv txhua lub vase thiab nkag siab thaum twg yuav muaj ntau dua 60 ntawm lawv. Hauv thawj lub vase peb muab 1 txiv duaj, hauv qhov thib ob - 2 txiv duaj, hauv peb - 3 txiv duaj, thiab lwm yam: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 = 66. Qhov no ntau dua cov txiv duaj uas peb muaj, yog li nws yuav tsis ua haujlwm los npaj lawv hauv 11 vases.

Qhov no txhais tau tias koj yuav tsum tau siv cov ntsiab lus tsawg dua (thiab tsawg dua vases): 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55. Qhov no tsawg dua 60. Qhov no txhais tau tias peb tuaj yeem ntxiv cov ploj lawm cov txiv duaj hauv qee lub vase: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 15 = 60. Txhua yam haum. Cov lus teb yog 10 vases.

Qhia teb Nthuav teb

2. Hais txog ib feem ntawm ice cream

Thaum Cheburashka noj ob qho dej khov nab kuab, Winnie the Pooh tswj noj tsib ntawm tib qho kev pabcuam, thiab thaum Winnie the Pooh noj peb zaug, Carlson noj xya. Ua hauj lwm ua ke, Cheburashka thiab Carlson noj 82 noj. Winnie the Pooh noj pes tsawg lub sijhawm no?

Cia peb them sai sai rau Winnie lub Pooh: nws yog los ntawm nws tias qhov ceev ntawm kev noj ice cream yog correlated los ntawm tag nrho cov heroes. Nrhiav qhov tsawg tshaj plaws ntau yam ntawm 3 (los ntawm qhov uas Winnie the Pooh muaj feem xyuam rau Carlson) thiab 5 (los ntawm qhov uas Winnie the Pooh muaj feem xyuam rau Cheburashka) - 15.

Qhov no txhais tau hais tias thaum Vinnie noj 15 servings ntawm ice cream, Cheburashka yuav noj 2 × 3 = 6 servings, thiab Carlson yuav noj 7 × 5 = 35 servings. Thaum Vinnie noj 15 servings ntawm ice cream, Cheburashka thiab Carlson ua ke rhuav tshem 6 + 35 = 41 servings. Lawv yuav noj 82 lub ncuav qab zib ob zaug, vim 82 ÷ 41 = 2. Qhov no txhais tau hais tias Winnie the Pooh yuav muaj sij hawm noj ob zaug ntau dua ib zaug: 15 × 2 = 30.

Qhia teb Nthuav teb

3. Hais txog Australian Zoo

Ntawm Australian Zoo, 35% ntawm tag nrho cov kangaroos yog grey, thiab 13% ntawm tag nrho cov tsiaj zoo yog kangaroos, tab sis tsis grey. Qhov feem pua ntawm tag nrho cov tsiaj hauv lub vaj tsiaj yog kangaroos?

Cia n yog tag nrho cov tsiaj hauv lub vaj tsiaj, c tus naj npawb ntawm cov kangaroos grey, thiab k tus naj npawb ntawm tag nrho cov kangaroos.

35% ntawm tag nrho cov kangaroos yog grey. Wb sau qhov no: 0, 35k = c.

13% ntawm tag nrho cov tsiaj tsis yog grey kangaroos. Peb kuj sau qhov no: 0, 13n = k - 0, 35k.

Cia peb ua kom yooj yim cov lus qhia: 0, 13n = 0, 65k; n:5k;ua. k = 1/5n = 20/100n = 20%. Qhov no txhais tau hais tias kangaroos muaj li 20% ntawm tag nrho cov tsiaj hauv lub vaj.

Qhia teb Nthuav teb

4. Hais txog gnome-liar

Muaj ob peb gnomes hauv chav uas ib txwm dag. Lawv yog cov sib txawv qhov siab thiab qhov hnyav sib txawv. Lawv txhua tus hais tias: "Txhua tus neeg sib dua li kuv, thiab qee qhov qis dua kuv." Qhov twg ntawm nqe lus A - D yog qhov tseeb?

A. Qhov hnyav tshaj plaws gnome - qis tshaj

B. Lub lightest gnome - qis tshaj

B. Qhov hnyav tshaj plaws yog qhov siab tshaj plaws

D. Lub lightest gnome yog qhov siab tshaj plaws

E. Tsis muaj ib nqe lus A txog D yuav tsum ua kom tiav.

Rau qhov hnyav tshaj plaws, lo lus "Txhua tus neeg sib dua li kuv" yog qhov tseeb, thiab nws txuas ntxiv - "… thiab ib qho ntawm lawv qis dua kuv" - yuav tsum yog lus dag. Yog li ntawd, tag nrho lwm cov dwarves siab dua nws. "Qhov hnyav tshaj gnome yog qhov qis tshaj" yog cov lus tseeb. Rau tag nrho lwm cov gnomes, kab lus "Txhua tus neeg sib zog dua kuv" twb yog lus dag, yog li tsis muaj dab tsi hais txog lawv.

Qhia teb Nthuav teb

5. Hais txog kev tsim ntawm Mad Hatter

Tus Mad Hatter ua lub moos coj txawv txawv. Lawv feeb tes yog nyob ruaj ruaj, thiab lub dial thiab teev tes tig kom lub moos ib txwm qhia lub sijhawm raug. Muaj pes tsawg lub kiv puag ncig ib hnub twg lub teev tes ntawm lub moos ua?

Lub feeb tes yog motionless. Txhawm rau kom nws qhia lub sijhawm kom raug, lub xov tooj yuav tsum txav mus rau qhov sib txawv (counterclockwise) ntawm tib lub nrawm raws li lub feeb tes txav mus rau hauv lub moos zoo tib yam, uas yog, ua kom muaj kev hloov pauv tag nrho hauv 1 teev, thiab 24 kiv puag ncig hauv. ib hnub.

Lub teev tes kuj yuav tsum qhia lub sij hawm kom raug. Ua ke nrog lub dial, nws yuav ua rau ib lub kiv puag ncig ib teev, uas yog, 24 kiv puag ncig ib hnub. Nws kuj mus nyob rau hauv nws cov kev coj ib txwm - ib tug tag nrho kiv puag ncig nyob rau hauv 12 teev thiab ob tag nrho revolutions nyob rau hauv 24 teev nyob rau hauv ib tug clockwise kev taw qhia. Yog li ntawd, thaum kawg, nws yuav ua rau 24 - 2 = 22 kiv puag ncig ib hnub.

Qhia teb Nthuav teb

Kev xaiv siv cov teeb meem los ntawm kev sib tw lej thoob ntiaj teb-kev ua si "Kangaroo" rau thiab xyoo.