Question

Daca ma ajutati la 3 probleme dau COROANA, dar daca ma ajutati la 4 probleme dau si PUNCTE

Answer 1

1.)

30:bx(b+5)=336

30b/b+150/b = 336

30b+150=336xb

336b-30b=150

306b=150

b=150/306=75/153=25/51 (am simplificat cu2 si apoi cu 3)

a = 30:25/51 =30x51/25=1530/25 =306/5 (am simplificat cu 5)

2.)

a+b = 4 x (a-b)

a+b+a-b=200

2 a =200

a = 200:2, a = 100

a+b = 4x (a-b)

100+b=400-4b

4b+b = 400-100, 5b = 300, b = 300:5 , b=60

3.)pa = pasi adult

pc = pasi copil

2 pa = 3pc

1 pc = 50 cm

2 pa = 150 m

2+3+2+3+....+2+3=2 (1+1+1...1) = 2x20 =40

40x50 = 2000cm= 20 m

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