Bonsoir besoin d’aide svp j’y arrive vraiment pas

1/
A=(65×47)+25=3080

2/
1100=2^2 × 5^2 ×11
3080=2^3 × 5 × 7×11

3/
a) A×B=2^2×5^2×11×2^3 × 5 × 7×11
=2^5 × 5^3 × 7× 11 ^2

b) A/B = 2^2×5^2×11/2^3 × 5 × 7×11
= 5/2×7 = 5/14

c) PGCD = 2^3 × 5^2 × 7 ×11
= 8 × 25 × 77 = 200 × 77 = 15400
4/
a)
1100= 11×100
3080= 11 × 280
b) 4180 = 1100+3080 = 11×100+ 11×280
On factorise par 11
4180 = 11 ×( 100 + 280 ) = 11 × 380

Bonne chance