Question

VA ROG AJUTATI-MA EXERCITIILE 12;14;16;17.

Answer 1

12)cate fete sunt in scoala?
$\frac{3}{5} din \: 1250$
$\frac{3}{5} \times 1250 = 1250 \div 5 \times 3 = \\ 250 \times 3 = 750 \: fete$
Cati băieți sunt?
1250-750=500 băieți


14)diagonala:4/10+5/10+9/10=18/10
18/10-4/10-6/10=8/10
18/10-6/10-9/10=3/10
18/10-8/10-5/10=5/10
18/10-5/10-3/10=10/10
18/10-9/10-5/10=4/10

Fiecare rand, coloana si diagonala sa fie 18 supra 10


35/10+14/100+16/100=65/100
65/100-14/100-19/100=32/100
Diagonala :65/100-35/100-19/100=11/100
65/100-16/100-11/100=38/100
65/100-38/100-19/100=8/100
65/100-32/100-11/100=22/100


16)
$\frac{2}{5} a = \frac{1}{3} b$
6a=5b
b---------l---------l---------l---------l--------l primul nr           }
Al---------l---------l---------l---------l--------l--------l al doilea }  330 suma

5+6=11 segmente
330:11=30 un segment
30x5=150 primul nr
30x6=180 al doilea nr

17)
$\frac{2}{3} \times 1263 = 126 3 \div 3 \times 2 \\ = 421 \times 2 = 842$
$\frac{1}{2} \times latime = 842$

latime=842x2=1684 m

$\frac{3}{5} \times 2500 = 2500 \div 5 \times 3 = \\ 500 \times 3 = 1500$
$\frac{1}{3} \times lungime = 1500$
Lungime=1500x3=4500 m
P=2x(L+l)
P=2x(4500+1684)
P=2x6184
P=12368



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