Question

ma ajuta cineva plz

Answer 1

d) a+a+1+a+2+a+3+a+4=75 5a+10=75 5a=75-10 5a=65 a=65:5=13 Nr sunt:13,14,15,16,17 e)a+1+a+3+a+5+a+7=72 4a+16=72 4a=72-16 4a=56 a=56:4=14 Nr sunt:15,17,19,21

Answer 2

d)

a + ( a + 1 ) + ( a + 2 ) + ( a + 3 ) + ( a + 4 ) = 75

5 x a + 10 = 75

5 x a = 75 -10

5 x a = 65

a = 65 : 5

a = 13 → primul numar

13 + 1 = 14 → al doilea nr.

13 + 2 = 14 → al treilea nr.

13 + 3 = 16 → al IV-lea nr.

13 + 4 = 17 → al V-lea nr. consecutiv

Raspuns:   13;  14;   15;   16;   17 → cele 5 numere consecutive, cu suma 75

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e)  

b + ( b + 2 ) + ( b + 4 ) + ( b + 6 ) = 72 → suma celor 4 numere impare consecutive

4 x b + 12 = 72

4 x b = 72 - 12

b = 60 : 4

b = 15 → primul numar impar

15 + 2 = 17 → al doilea nr. impar

17 + 2 = 19 → al III -lea nr. impar

19 + 2 = 21 → al IV -lea nr. impar consecutiv

15 + 17 + 19 + 21 = 72 → suma celor 4 numere impare consecutive