1 00:00:00,050 --> 00:00:01,850 La inceputul saptamanii 2 00:00:01,850 --> 00:00:03,783 contul curent al lui Stewart avea un sold 3 00:00:03,783 --> 00:00:07,200 negativ de 15 dolari si 8 centi. 4 00:00:07,200 --> 00:00:09,800 Luni dimineata a depus un cec 5 00:00:09,800 --> 00:00:12,733 de 426 dolari si 90 de centi. 6 00:00:12,733 --> 00:00:15,488 Marti dimineata a depus un alt cec 7 00:00:15,488 --> 00:00:17,160 de o suta de dolari. 8 00:00:17,160 --> 00:00:19,692 Ce suma se afla in contul curent al lui Stewart 9 00:00:19,692 --> 00:00:24,861 dupa cel de-al doilea depozit, deci dupa amandoua depozitele de aici? 10 00:00:24,861 --> 00:00:27,237 Deci incepe cu un sold negativ, 11 00:00:27,237 --> 00:00:28,200 un sold negativ inseamna 12 00:00:28,200 --> 00:00:31,131 ca a cheltuit mai mult decat avea disponibil in cont. 13 00:00:31,131 --> 00:00:32,017 De fapt, este dator bancii acum. 14 00:00:32,017 --> 00:00:34,918 Din fericire, acum o sa puna bani in contul sau, 15 00:00:34,918 --> 00:00:38,615 drept urmare va avea un sold pozitiv in contul curent. 16 00:00:38,615 --> 00:00:43,467 El incepe cu o datorie de 15 dolari si 8 centi, 17 00:00:43,467 --> 00:00:45,302 iar la aceasta adauga 18 00:00:45,302 --> 00:00:49,889 426 dolari si 90 de centi. 19 00:00:49,889 --> 00:00:51,867 Apoi adauga inca o suta de dolari. 20 00:00:52,317 --> 00:00:59,791 Deci, a inceput cu un minus de 15 dolari si opt centi, 21 00:00:59,791 --> 00:01:03,507 la care adauga 426 dolari 22 00:01:03,507 --> 00:01:04,867 si 90 de centi si 100 de dolari. 23 00:01:04,867 --> 00:01:09,358 Asta inseamna 526 si 90 de centi. 24 00:01:09,358 --> 00:01:11,473 Drept urmare, ce suma va avea in contul sau? 25 00:01:11,473 --> 00:01:14,838 A inceput cu o datorie de 15 dolari si opt centi, 26 00:01:14,838 --> 00:01:15,674 iar la aceasta adauga 27 00:01:15,674 --> 00:01:18,832 526 dolari si 90 de centi. 28 00:01:18,832 --> 00:01:20,086 Un mod de a privi problema 29 00:01:20,086 --> 00:01:23,000 este sa ne gandim la ea pe o axa a numerelor, 30 00:01:23,250 --> 00:01:25,798 cu zero aici. 31 00:01:25,798 --> 00:01:31,000 El incepe la punctul -15.08, 32 00:01:31,000 --> 00:01:32,160 la care va adauga 33 00:01:32,160 --> 00:01:37,222 526 dolari [si 90 de centi]. 34 00:01:37,222 --> 00:01:40,733 La stanga avem 15.08, 35 00:01:40,733 --> 00:01:41,817 suma pe care o datoreaza, 36 00:01:41,817 --> 00:01:43,631 iar la aceasta va adauga 37 00:01:43,631 --> 00:01:46,333 526 [dolari si 90 de centi]. 38 00:01:46,333 --> 00:01:47,950 Nu desenez acest lucru la scala, 39 00:01:47,950 --> 00:01:49,203 dar la suma aceasta va adauga 40 00:01:49,203 --> 00:01:54,358 526 dolari si 90 de centi. 41 00:01:54,358 --> 00:01:55,962 Deci, soldul pozitiv pe care il va avea 42 00:01:55,962 --> 00:01:57,284 va fi 43 00:01:57,284 --> 00:01:59,420 526 dolari si 90 de centi 44 00:01:59,420 --> 00:02:02,021 minus 15.08. 45 00:02:02,021 --> 00:02:03,275 Drept urmare va fi distanta aceasta, 46 00:02:03,275 --> 00:02:09,726 aceasta suma va fi pozitiva. 47 00:02:09,726 --> 00:02:13,733 Va fi 526,90 48 00:02:13,733 --> 00:02:16,510 minus 15,08 49 00:02:16,510 --> 00:02:17,467 Deci va fi - 50 00:02:17,467 --> 00:02:20,225 si putem sa rescriem aceasta 51 00:02:20,225 --> 00:02:21,851 ca sa arate asa. 52 00:02:21,851 --> 00:02:24,219 Este exact acelasi lucru precum 53 00:02:24,219 --> 00:02:26,495 526,90 54 00:02:26,495 --> 00:02:27,076 minus - 55 00:02:27,076 --> 00:02:27,656 minus - 56 00:02:27,656 --> 00:02:31,928 sa adaugi un numar negativ este acelasi lucru 57 00:02:31,928 --> 00:02:32,883 cu a scadea un numar pozitiv - 58 00:02:32,883 --> 00:02:35,267 minus 15,08 59 00:02:35,267 --> 00:02:37,200 - O sa scriu asta cu alta culoare - 60 00:02:37,200 --> 00:02:40,200 526,90 61 00:02:40,200 --> 00:02:43,956 minu 15,08. 62 00:02:43,956 --> 00:02:46,557 Sa vedem, zero este mai mic decat opt, 63 00:02:46,557 --> 00:02:48,972 facem din acesta un zece si imprumutam de la noua 64 00:02:48,972 --> 00:02:50,551 asa incat acesta devine 8 - 65 00:02:50,551 --> 00:02:51,619 sau as putea spune ca regrupam - 66 00:02:51,619 --> 00:02:54,173 Totul de aici este mai mare decat totul de acolo, 67 00:02:54,173 --> 00:02:56,356 deci zece minus opt e doi, 68 00:02:56,356 --> 00:02:58,445 opt minus zero e opt, 69 00:02:58,445 --> 00:02:59,421 si avem zecimalele. 70 00:02:59,421 --> 00:03:01,603 Sase minus cinci e unu, 71 00:03:01,603 --> 00:03:04,111 Doi minus unu e unu, 72 00:03:04,111 --> 00:03:06,067 si apoi ai cinci minus nimic. 73 00:03:06,067 --> 00:03:07,640 Deci a ramas 74 00:03:07,640 --> 00:03:10,733 cu 511 dolari si 82 de centi, 75 00:03:10,733 --> 99:59:59,999 dupa cel de-al doilea depozit.