Gabriel had u friends.

He gave away 5u nuggets and 4u biscuits.

At first he had (5u + 5) nuggets and (4u + 70) biscuits.

Since biscuits was twice of nuggets,

2 x (5u + 5) = 4u + 70

10u + 10 = 4u + 70

6u = 60

u = 10

(a) Gabriel had 10 friends 

Nuggets -> 5u + 5 = 55

(b) Gabriel bought 55 more biscuits than nuggets

(a)

(5  x number of friends + 5) x 2 = 10 x number of friends + 10 ——- 4 x number of friends + 70

6 x number of friends ——– 70 – 10 = 60

number of friends ——- 60/6 = 10

(b)

5 x 10 + 5 = 55 (nuggets)

or

4 x 10 + 70 = 110 (biscuits)

110/2 = 55

Ans : (a) 10 friends; (b) 55 more biscuits.