Yuav ua li cas yuav ua rau ib tug kev faib ua feem? To taub txhua txhua tus menyuam kawm ntawv thiab cov laus

Nyob rau hauv thiaj li yuav daws tau feem ntau ntawm cov teeb meem nyob rau hauv nruab nrab lub tsev kawm ntawv kev kawm txog zauv paub tsim nyog rau cov muab tso ua ke ntawm proportions. Qhov no yooj yim kev txawj yuav tsis tau tsuas yog nqa tawm complex ce nyob rau hauv cov phau ntawv nyeem, tab sis kuj delve rau hauv lub essence ntawm kev kawm txog zauv. Yuav ua li cas yuav ua rau ib tug kev faib ua feem? Tam sim no peb tsom xam.

Qhov yooj yim piv txwv yog lub teeb meem ntawm qhov chaw uas peb tsis paub, thiab plaub yuav tsum tau pom. Lub proportions yog, ntawm chav kawm, sib txawv, tab sis feem ntau yuav tau mus nrhiav paj tus lej twg. Piv txwv li, tsuas yog tus me nyuam tub yog kaum apples. Qhov thib plaub ib feem nws tau muab rau nws niam. Yuav ua li cas muaj ntau yam apples nyob rau hauv lub me nyuam tub? Qhov no yog ib tug heev yooj yim piv txwv uas yuav ua rau kev faib ua feem. Qhov loj tshaj plaws ua rau nws. Chiv, nws yog kaum apples. Cia nws 100%. Qhov no yog li cas peb tau xaiv tag nrho cov ntawm nws apples. Nws muab ib feem plaub ntawm. 1/4 = 25/100. Yog li ntawd nws tau sab laug: 100% (Ameslikas) - 25% (nws muab) = 75%. Qhov no xam pom tias qhov feem pua ntawm seem nyiaj ntawm txiv hmab txiv ntoo rau cov xov tooj ntawm muaj ua ntej. Tam sim no peb muaj peb tus xov tooj, uas yog twb tau los mus daws cov kev faib ua feem. Apples 10 - 100%, x apples - 75%, qhov twg x - cov yam nqi ntawm txiv hmab txiv ntoo. Yuav ua li cas yuav ua rau ib tug kev faib ua feem? Nws yuav tsum tau to taub hais tias nws yog. Lej, nws zoo li no. Nws txo nws hwj ib qhov sib npaug kos npe rau koj to taub.

10 = 100% Kua;

apples x = 75%.

Nws zoo nkaus li uas lub 10 / x = 100% / 75. Qhov no yog qhov yooj yim proportions ntawm cov cuab yeej. Qhov ntau x, ntau dua qhov lub feem pua ntawm tus xov tooj ntawm tus thawj. Peb daws tau qhov kev faib ua feem, thiab peb pom tias x = 7,5 apples. Vim li cas cov me nyuam tub txiav txim siab los muab ib tug uas tsis yog-integer tooj, peb tsis paub. Tam sim no koj paub yuav ua li cas mus cuag kev faib ua feem. Qhov loj tshaj plaws yog mus nrhiav ob ratios, yog ib tus uas yog tus yam tsis paub hais tias.

kev faib ua feem ntawm qhov kev txiav txim feem ntau los mus ua ib tug yooj yim multiplication, thiab ces mus rau faib. Nyob rau hauv tsev kawm ntawv, cov me nyuam tsis qhia vim li cas qhov no yog li ntawd. Thaum nws yog ib qho tseem ceeb kom nkag siab txog hais tias cov proportional kev sib raug zoo yog ib tug zauv classics, cov essence heev ntawm science. Yuav kom daws tau proportions yuav tsum tau mus nrog cov zauv feem. Piv txwv li, feem ntau muaj txhais paj mus rau hauv zoo tib yam fractions. Qhov ntawd yog ib cov ntaub ntawv ntawm 95% yuav tsis ua hauj lwm. Thiab yog hais tias tus sau ib zaug 95/100, cov khoom yuav txo tau yuav nqa tawm tsis muaj pib lub ntsiab suav. Tam sim ntawd nws yuav tsum hais tias yog hais tias koj piv tau muab nyob rau hauv ob unknowns, nws yuav tsis tau solved. Tsis xib fwb no yuav pab tsis tau koj. Thiab koj ua hauj lwm yog yuav muaj ib tug ntau algorithm rau tseeb ua.

Xav txog lwm cov piv txwv, qhov muaj yog tsis muaj paj laum. Tsav tsheb yuav 5 litres ntawm petrol rau 150 rubles. Nws xav li cas txog ntau npaum li cas nws yuav tau them rau 30 litres ntawm cov roj. Yuav kom daws tau qhov teeb meem no rau x txhais cov kev kawm npaum li cas ntawm cov nyiaj. Koj muaj peev xwm ntawm nws tus kheej kom daws tau qhov teeb meem, thiab ces mus saib cov lus teb. Yog hais tias koj tsis tau xam tau tawm li cas yuav ua rau ib tug kev faib ua feem, ces saib. 5 litres ntawm cov roj av - yog 150 rubles. Raws li nyob rau hauv thawj Piv txwv li, lub sau 5l - 150r. Tam sim no peb nrhiav tau peb tus xov tooj. Ntawm cov hoob kawm, nws yog 30 liters. Pom zoo hais tias cov khub 30 L - x rubles tsim nyog nyob rau hauv ib tug muab qhov teeb meem no. Mus rau cov lus ntawm kev kawm txog zauv.

5 litres - 150 rubles;

30 litres - x rubles;

5/30 = 150 / x.

Daws tau qhov kev faib ua feem:

5x = 30 * 150;

x = 900 rubles.

Yog li ntawd, kev txiav txim siab. Nyob rau hauv nws cov hauj lwm yuav tsum xyuas rau lub adequacy ntawm lub teb. Nws tshwm sim hais tias thaum lub tsis ncaj ncees lawm kev txiav txim siab tsheb mus txog speeds unrealistic mus 5,000 kilometers ib teev, thiab hais txog. Tam sim no koj paub yuav ua li cas mus cuag kev faib ua feem. Tsis tas li ntawd koj yuav tsum tau mus daws tau. Raws li koj tau pom, qhov no yog tsis muaj big deal.