CONSTRAINTS HELP!

Mr. Weber drives to a landscape supply center to buy sand and gravel. The center has 6 lb of sand and 13 lb of gravel in stock. Mr. Weber needs at least 2 lb of sand. The amount of gravel he will buy will be at least twice the amount of sand he will buy.

Mr. Weber buys 7 lb of gravel. How much sand can he buy?

Choose all answers that are correct.

A 2 lb
B 3 lb
C 4 lb
D 5 lb
E 6 lb

Respuesta :

I think the answer is B
Mr. Weber has bought 7 lbs of gravel and he must buy at least 2 lbs of sand. 
Also:  G ≥ 2 · S
7 ≥ 2 · 2
7 ≥ 2 · 3
Answer:
Mr. Weber can buy : A ) 2 lb or B ) 3 lb of sand.