Some of these squares are to be shaded so that:

(i) at least 2 squares are shaded

(ii) two squares meeting along an edge or at a corner are not both shaded.

**How many**ways are there to do this?

Kindly provided by UKMT The figure shown above is made from 7 small squares.
Some of these squares are to be shaded so that: (i) at least 2 squares are shaded (ii) two squares meeting along an edge or at a corner are not both shaded. How many ways are there to do this?
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Kindly provided by M4ths.com ## GCSE Question for Higher students. Knowledge of 3 topics required and should appeal to B/A+ candidates. Kindly provided by UKMT A point is marked one quarter of the way along each side of a triangle, as shown. What fraction of the area of the triangle is shaded? A bag contains m blue and n yellow marbles. One marble is selected at random from the bag and its colour is noted. It is then returned to the bag along with k other marbles of the same colour. A second marble is now selected at random from the bag. What is the probability that the second marble is blue? Kindly provided by Pierre Bierre Search and Rescue... Your personal aircraft suffered a power failure, forcing you to emergency-land in the desert. “Where am I?” You recognize two mountain peaks with known map (x,y) coordinates: Peak1: (-100, 0) Peak2: (100, 0) From your vantage, the angle subtended by the two peaks is 49.000 degrees, with left-to-right order [ Peak2 …… Peak1 ]. You only have enough cell phone battery remaining to phone in this one clue: What is the curve that should be flown by a search and rescue chopper that will pass over your location? Provide the numerics to precisely define your curve.
Three circles and the lines PQ and QR touch as shown.The distance between the smallest and the biggest circles is 16 times the radius of the smallest circle. What is the size of angle PQR?
Kindly provided by UKMT Beatrix has a 24-hour digital clock on a glass table-top next to her desk. When she looked at the clock at 13:08, she noticed that the reflected display also read 13:08 (as shown above).
How many times in a 24-hour period do the display and its reflection give the same time? |
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March 2017
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