On a Tube train approaching Farringdon the passengers were struck by sheets of discarded wrapping paper on the floor of the carriage. Turned out a less thoughtful newspaper was giving away giftwrap.

Tut. Tut. What we need in these green times is less wrapping paper, not more. Warwick Dumas, of the department of mathematics at Leicester University, has invented a formula that “proves that consumers can still wrap their presents without using excess paper”.

He explains it like this. “In the most simplistic terms the minimal area of paper needed to wrap a box-shaped gift is twice the sum of the height times the width, the width times the depth and the height times the depth, plus twice the square of the depth. We have tested different methods of wrapping and our investigations showed that using the largest side as the base and cutting the right size of paper will allow consumers to wrap presents in the least amount of time and achieve a classy result.”

Further: “Wrapping a cuboid diagonally uses strictly more paper than wrapping the traditional way except for an item with a square base, but wrapping diagonally uses a different shape of paper and so could be useful when only a small piece is left. When wrapping “diagonally”, 45 degrees is the best azimuth as long as where a>b>c are the dimensions of the item. Otherwise the best angle is such that the flaps only just meet.”

For a cylinder, a rotational method of wrapping was tried but “when the radius is greater than about 0.876 of the height (actually, h/(pi-2)), it is better to wrap the item as a cuboid”.

Couldn’t be simpler.

Alternatively, one could use the ultimate in high-end, recycled wrapping paper: a copy of yesterday’s Times.

Times recommends

• Babyboomers still partying on in their sixties
• Do I have a chance of finding love again?
• Video: How to do party make-up