A buffer reserves some available money for unexpected costs, but a surprise can cost more than the buffer.

For the months being planned, rent stays at the same amount while food spending changes. How should these costs be classified?

• Rent is fixed; food is variable
• Rent is variable; food is fixed
• Rent and food are both fixed costs

Monthly income after deductions is £150. Fixed bills need £50 and variable spending £60. Which saving and buffer amounts complete a £150 plan?

• Savings £30 and buffer £20
• Savings £25 and buffer £15
• Savings £40 and buffer £15

Travel spending was planned at £75 and actually came to £90. What percentage of the planned £75 is the increase? Enter the percentage number.

Food spending was planned at £45 and actually came to £57. How many pounds above plan was it?

Travel exceeded the plan because a cancelled bus led to one taxi fare. The usual bus cost has not changed. What does this record tell you?

• Raise every future month's travel plan by the taxi fare
• This gap came from a one-off event
• Remove travel from future plans because the amounts differed

Income is £200. The plan has food £60, other required costs £80, fun £30, saving £20 and buffer £10. Records show food now regularly needs £75. Income stays the same. Which revision balances?

• Raise food to £75 and leave every other allocation unchanged
• Keep food at £60 and lower fun to £15 despite the recorded need
• Raise food to £75 and lower fun to £15; keep the other amounts

Food is £15 above a £50 plan, or 30%. Rent is £15 above a £1,000 plan, or 1.5%. What follows from comparing these percentages?

• Food must be cut first, regardless of needs or payment dates
• The rent gap can be ignored because its percentage is small
• Food has the larger gap relative to its plan