First we need to found out how many pounds and luggage to small plane can carry, now that we know there is 490 pounds of mail.
1050 - 490 = 560
Now we need to find out the maximum number of passengers that can board the plane.
70p = 1050
We know that there are 560 avalible pounds left on the plane
70 x 8 = 560
560 + 490 = 1050.
Well if we go back to the question it says less than 1050. This means that 8 passengers times 70 pounds each would not be correct because the small airplane can carry less than 1050 pounds.
70 x 7 = 490
490 + 490 = 980
980 is less than 1050
So the answer would be 7 passengers.
7 Passengers is the maximum amount of passengers that can be taken.
I hope this helps!