#163 Down for the count
In the TV number quiz show Down for the Count, four contestants are challenged to combine each of five number cards exactly once to achieve a target number. They are allowed to use standard arithmetical operations +, -, 脳 and 梅 (as well as brackets, if required).
鈥淚鈥檒l take five cards from the top row,鈥� requested one of the contestants, and the presenter Anne-Marie obligingly revealed these five numbers:
10; 100; 1000; 10,000; 100,000.
The studio computer then generated today鈥檚 challenge: 鈥淧roduce a whole number without any zeroes.鈥�
No zeroes? Wow. Each of the four contestants thought hard, and after the timer ran out, each announced that they had used the five cards to produce a positive number smaller than 10. All four were different.
Which numbers did they get, and how?
Solution next week
#162 Poker dice
Solution
The opposing faces of a die always add up to 7. Therefore, the die that is on the extreme right must present 5 to the adjoining cube.
The central five dice contribute another 5 x 7 = 35 to the total, regardless of their orientation.
The die on the furthest left has 6 on top and 1 on the bottom, and by comparing the orientation of the 2 with that on the die at the right, the furthest left die must present a 4 to the adjoining cube.
Hence the total of the touching faces is: 5+35+4=44.
Quick quiz #147
1 Sunflowers and dahlias belong to which plant family?
2 The increase in wavelength of X-rays or gamma rays that occurs when they are scattered is known as what?
3 Which geological epoch began approximately 11,700 years ago?
4 Eridu and Larak were city states in which ancient civilisation?
5 Pioneer 10 was the first spacecraft to visit which planet?
Answers below
Quick quiz #147
Answers
1 Asteraceae, commonly known as the daisy family
2 The Compton effect
3 The Holocene
4 Sumer
5 Jupiter