#170 Presents, but not correct
鈥淗ave you written your thank-you letters, Kayleigh?鈥�
鈥淣ot yet mum, just doing it now. Do I thank Amelia for the nail varnish, Beth for the book, Clara for the lip balm, Diaz for the pencils and Elinor for the sunglasses?鈥�
鈥淎t least four of those are wrong.鈥�
鈥淎h, then was it Amelia for the book, Beth for the lip balm, Clara for the pencils, Diaz for the nail varnish and Elinor for the sunglasses?鈥�
鈥淭hat鈥檚 better, but you鈥檝e still made mistakes.鈥�
鈥淗ow about Amelia for the lip balm, Beth for the sunglasses, Clara for the pencils, Diaz for the book and Elinor for the nail varnish?鈥�
鈥淓ven better, but still not full marks. Clara didn鈥檛 give you the pencils or the sunglasses.鈥�
鈥淚 give up.鈥�
Can you help?
#169 A Domino Piazza
Solution
A full set of dominoes has eight of each number. In the piazza, there are eight 0s and 1s, and seven 2s, 3s, 5s and 6s, so we can be sure that the 0-0, 1-1, 2-2, 3-3, 5-5 and 6-6 dominoes all appear.
6-6 and 0-0 can be identified immediately, which forces 5-6 (bottom left) and 5-3 (bottom right), so barriers can now be drawn between any other 5-3 and 5-6 pairs, and 5-5 must be in the top row. From this the whole pattern can be found. The missing dominoes are 4-4, 4-2, 5-4 and 6-3.
Quick quiz #154
1 Chiropterophily is the pollination of plants by which animals?
2 In what year was the US space station Skylab launched?
3 Name the first human virus to be discovered.
4 A sphygmomanometer is used to measure what?
5 In which US state would you find the largest flat-topped mountain, or mesa, in the world?
Answers
1 Bats
2 1973
3 Yellow fever virus
4 Blood pressure
5 Colorado. The Grand Mesa covers around 1300 square kilometres