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- What would the total be if you add ‘all’ the numbers in the first 200 consecutive numbers (i.e., 1 + 2 + 3 + 4 + 5 + etc.)?
- What would the total be if you add all the ‘even’ numbers in the first 200 consecutive numbers (i.e., 2 + 4 + 6 + 8 + 10 + etc.)?
- What would the total be if you add all the ‘odd’ numbers in the first 200 consecutive numbers (i.e., 1 + 3 + 5 + 7 + 9 + etc.)?
MIND-Xpander (‘Circles in a Rectangle’ Challenge – Level 1)
The diagram below shows two identical circles touching each other and completely put inside a rectangle (as shown below). The circles are not over-lapping and each touches two sides of the rectangle (as shown). What are the dimensions of the rectangle if their radius is 5cm? Note: The diagram is not drawn to scale.
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Last month's solutions
In the following puzzle, there is a common arithmetic relationship between the set of equations that allow their respective solutions as shown. Determine the relationship to find the unknown relational value (?).
1 + 4 (x1 – 0) = 5
2 + 5 (x2 – 1) = 11
3 + 6 (x3 – 2) = 19
5 + 8 (x5 – 4) = 41
MIND-Xpander (Circular Logic Challenge – Level 1)
You have 50 sticks standing upright in a circle (#1 to #50). Starting with stick #1, knock over the next stick (#2) in the circle. Then continue by knocking over every second stick (next is #4). Keep going around and around the circle until one stick remains standing. What number is the last stick standing?
What if you start with stick #4 and continue in same manner as above?
Solution 1: Solution 2: