Performance mngt and control

Sir, please help me with the following problem -kaplan kit (exp. June 2016 ), 289 (Woodside charity)

Woodside is a local charity. Fund rising target $700000. The budget for last year based on following forcast:

free meals – 18250 meals at $5
overnight shelter – 10000 bed night’s at $30
advice centre – 3000 sessions at $20
campaigning and advertising – $150000

Actual funds raised- $620000

Operating statement:
budget surplus 98750
funding shortfall (80000)
Net 18750

variancies:

FREE MEALS
price 4000(A)
usage 8750 (A)

OVERNIGHT SHELTER
price 4380 (A)
usage 31000 (F)

ADVICE CENTER
price 9100 (A)
usage 7500 (A)

CAMPAIGNING AND ADVERTISING
expenditure 15000 (A)

FIXED COSTS
expenditure 18000 (A)

Actual total (16980)

In workings it is indicated:
Free meals provision cost 12750 (14%) more than budgeted. Is this a 14% of 18250 * 5?
Then, variable cost of overnight shelter 26620 (11%) less than budgeted. Why 11%?
Variable advice centre 16600 (37%) above budget. Why 17%?
This was due to increased usage of service which was up from 3000 to 3500( Where is this described in problem? )
and average cost rising from $15 to $17. 60( Where is this described in the problem? )