Yuav ua li cas thiaj li paub suav kom sai sai hauv lub siab?

Cov txuj ci uas tau txais los ntawm cov lus qhia ntawm algebra thiab geometry hauv lub neej tib neeg siv tsis tshua muaj xwm txheej. Qhov tseem ceeb tshaj plaws thiab yuav tsum muaj kev txawj ntse nrog kev ua lej yog qhov peev xwm sai sai rau hauv lub siab, yog li nws yog qhov zoo tsim nyog los paub txog kev yuav kawm li cas. Nyob rau hauv lub neej hauv lub neej, qhov no cia koj mus ceev nrooj xam qhov kev hloov, xam lub sij hawm, thiab lwm yam.

Nws yog qhov zoo tshaj plaws los tsim cov peev xwm los ntawm cov menyuam yaus, thaum lub hlwb kawm tau ntawv ceev dua. Muaj ntau cov tswv yim zoo uas ntau tus neeg siv.

Yuav ua li cas thiaj li paub suav kom sai sai hauv lub siab?

Ua kom tiav cov txiaj ntsim tau zoo, nws yog ib qho tsim nyog rau kev xyaum ua ntu zus. Tom qab ua tiav cov hom phiaj, nws tseem muaj nqis rau txoj haujlwm. Ntawm qhov tseem ceeb yog lub peev xwm ntawm ib tug neeg, uas yog, lub peev xwm los khaws ntau yam hauv kev nco thiab mloog zoo. Txoj kev vam meej loj tshaj plaws yuav ua tiav los ntawm cov neeg uas muaj lub zauv hlwb. Yuav kom sai sai rau kev suav, koj yuav tsum paub lub rooj sib npaug ntawm qhov sib npaug.

Cov txheej txheem nrov tshaj plaws ntawm kev suav:

  1. Peb xav paub tias yuav ua li cas thiaj li yuav ntsuas ob tug zauv hauv lub hlwb, yog tias koj xav kom muab los ntawm 11. Yuav kom nkag siab txog cov txheej txheem, peb saib ib qho piv txwv: 13 qhov lem los ntawm 11. Qhov teeb meem yog qhov ntawm cov naj npawb 1 thiab 3 koj yuav tsum sau lawv cov nqi, yog 4. Yog li ntawd, nws hloov tawm tias 13 x 11 = 143. Thaum tus lej ntawm tus lej muab ob tug lej, piv txwv li, yog tias koj khwv tau 69 rau 69, ces 6 + 9 = 15, ces koj tsuas yog khij ob tus lej, uas yog, 5, thiab ntxiv rau thawj tus lej ntawm tus zauv. Nws muaj lwm txoj kev los muab tus naj npawb los ntawm ntau dua los ntawm 11. Txij thaum pib, muab los ntawm 10, thiab tom qab ntawd ces ntxiv rau tus naj npawb thawj rau nws. Piv txwv, 14x11 = 14x10 + 14 = 154.
  2. Lwm txoj kev los suav cov naj npawb ntawm ntau tshaj hauv lub hlwb ua hauj lwm rau kev sib npaug ntawm kev ua lej 5. Txoj cai no tsim nyog rau txhua tus lej uas yuav tsum tau muab faib ua ntej 2 rau qhov pib.Yog li qhov tshwm sim, koj yuav tsum muab xoom rau qhov kawg. Piv txwv, kom paub tias ntau npaum li cas 504 yuav tsum tau multiplied by 5. Ua li no, 504/2 = 252 thiab yog vim li cas ntawm qhov kawg ntawm 0. Vim li ntawd, peb tau txais 504 x 5 = 2520. Yog tias, thaum faib ib tug zauv, koj tsis tau txais ib qho integer, koj tsuas yog xav tshem tawm cov comma. Piv txwv, kom paub tias muaj pes tsawg zaus 173 multiplied by 5, koj xav tau 173/2 = 86.5, thiab tom qab ntawd tshem tawm cov comma, thiab nws lem tawm ntawd 173 x 5 = 865.
  3. Peb kawm paub yuav ua li cas thiaj li xam ob tug lej, ob qhov ntxiv. Ua ntej koj yuav tau ntxiv kaum, thiab tom qab ntawd, cov units. Yog xav tau qhov kawg, koj yuav tsum tau ntxiv qhov thib ob tshwm sim. Piv txwv li, peb mam li txiav txim siab tias yuav pes tsawg li 13 + 78 xyoo. Thawj kauj ruam: 10 + 70 = 80, thiab ob: 3 + 8 = 11. Qhov kawg tshwm sim yog raws li nram no: 80 + 11 = 91. Txoj kev no siv tau thaum muaj ib qho sib nrauj los ntawm ib tus lej.

Lwm qhov tseem ceeb yog qhov sai npaum li cas los xam cov feem pua ​​hauv hlwb. Rov ua dua, rau qhov kev nkag siab zoo, xav txog ib qho piv txwv txog kev nrhiav 15% ntawm tus nab npawb. Ua ntej, txiav txim siab 10%, uas yog, sib faib los ntawm 10 thiab ntxiv ib nrab ntawm cov txiaj ntsig -5%. Nrhiav 15% ntawm 460: mus nrhiav 10%, sib faib tus naj npawb los ntawm 10, peb tau txais 46. Cov kauj ruam tom ntej yog los nrhiav ib nrab: 46/2 = 23. Yog li ntawd, 46 + 23 = 69, uas yog 15% ntawm 460.

Nws muaj lwm txoj hau kev, xam cov paj laum. Piv txwv, yog tias koj xav tau los txiav txim xyuas seb yuav npaum li cas 6% ntawm 400. Yuav pib, nws yog qhov yuav tsum paub txog 6% ntawm 100 thiab qhov no yuav yog 6. Mus nrhiav 6% ntawm 400, koj xav tau 6x4 = 24.

Yog tias koj yuav tsum nrhiav 6% ntawm 50, ces koj yuav tsum siv qhov kev siv algorithm: 6% ntawm 100 yog 6, thiab rau 50, qhov no yog ib nrab, uas yog 6/2 = 3. Yog li ntawd, nws hloov tawm tias 6% ntawm 50 yog 3.

Yog hais tias tus naj npawb ntawm qhov koj xav tau kom nrhiav tau ib feem pua ​​tsawg tshaj 100, koj tsuas yog yuav tsum tau tawm ntawm lub voos xwm txheej mus rau sab laug. Piv txwv, nrhiav 6% ntawm 35. Ua ntej, nrhiav 6% ntawm 350 thiab nws yuav yog 21. Tus nqi ntawm tib 6% rau 35, yog 2.1.