o gaina +un iepure =7kg​

i -> iepure

g -> găină

p -> porc

g + i = 7 kg

p - g = 53 kg

i + i + i = 15 kg

g + p + i = ? kg

______

i + i + i = 15

=> 3×i = 15 | ÷ 3

=> i = 15÷3 = 5 kg

g + i = 7 kg

=> g + 5 = 7 kg | - 5

=> g = 7 - 5

=> g = 2 kg

p - g = 53 kg

=> p - 2 = 53 kg | + 2

=> p = 53 + 2

=> p = 55 kg

g + p + i =?

=> 2 + 55 + 5 = ?

=> 57 + 5 = ?

=> = 62 kg

Răspuns:

Explicație pas cu pas:Stii ca 3 iepuri =15 kg  => 1 iepura =15:3=5Kg

atunci g+5=7=> g=7-5=2 kg gaina

p-2kg =53 => p=53+2=55 kg porcul

2+55+5=62 kg impreuna

2) 2 pupeze= 18

18:2=9 g o pupaza

b+9= 69

b=69-9=60 barza

v+9=29

v=29-9=20 vrabia

60-20+9= 49

3.

60-30=30 lacusta

60-50=10 fluturele

60-(30+10)=60-40= 20