45 (number)

45 was a number.

Frobisher was 45 years old when he met the Sixth Doctor. (COMIC: The Shape Shifter)

The Doctor left primary school at the age of 45. (PROSE: Shroud of Sorrow)

Mrs Crisp aimed to make the IQ of everybody 45 but she was stopped by the Seventh Doctor, Ace and Hex. (AUDIO: Order of Simplicity)

There were 45 cousins in the House of Lungbarrow on Gallifrey, including the Doctor. (PROSE: Cat's Cradle: Time's Crucible, Lungbarrow)

From his appearance, Jackie Tyler suggested that the Ninth Doctor was 40 or 45 years old. (TV: Aliens of London)

Chronon, (WC: 14682 UNIT Field Log, 14683 UNIT Field Log, 14684 UNIT Field Log) or cronon (WC: 14681 UNIT Field Log) and artron energy readings during the recording of UNIT field logs included 17%, (WC: 14682 UNIT Field Log) 18%, 19%, (WC: 14681 UNIT Field Log, 14682 UNIT Field Log) 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, (WC: 14682 UNIT Field Log) 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, (WC: 14682 UNIT Field Log, 14684 UNIT Field Log) 90%, (WC: 14682 UNIT Field Log, 14683 UNIT Field Log) 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 100%, 101%, 102%, 103%, 104%, 105%, 106%, and, in the case of Chronon energy, 107%. (WC: 14683 UNIT Field Log)

Behind the scenes
While unreadable in the episode itself, the copy of the Western Mail featured in Boom Town gives Margaret Blaine's age as 45 as of September 2006. The reference book The Doctor: His Lives and Times, which contains in-universe, narrative material whilst also having a large focus on out-of-universe material, includes a further Western Mail article which states that Blaine is 56.