A Tricky 'n' Easy Maths Quiz! (2)

Answer: 5 and 2

Now that was easy! The mode of a set of numbers is the number that occurs most frequently. In this case ( 10 9 8 7 5 5 4 3 2 2 ), 5 and 2 occur most frequently.

Answer: 39/52 = 3/4

There are 13 cards which are clubs, therefore the number of cards that are not clubs is 52-13, or 39. Therefore the probability that it does not belong to the suit of clubs is 39/52 or 3/4 (simplified).

Answer: 2 cm

We know that the formula for finding the area of a triangle is:
A = 1/2 * b * h (where A is area, b is the base and h is the perpendicular height)
0.36 metres = 36 centimetres.
Now we can plug in the numbers:
36 = 1/2 * b * 36
36 = 18b
36/18 = b
b = 2.
Check: If the base is 2 cm and the perpendicular height is 36 cm, then the area is 1/2 * 2* 36 = 36 cm^2. Notice that we do not need the slant height.

Answer: 15 days

Three men build a wall in 10 days. Therefore 1 man takes 3*10 days or 30 days (This is a question involving inverse proportion). 2 men take 30/2 days or 15 days to build a wall.
Check:
1 man takes 30 days to build a wall.
2 men take 15 days to build a wall.
3 men take 10 days to build a wall.
Therefore, the more men, the less time.

Answer: 9

We all know that the word "of" in mathematics means "multiply" and a minute consists of 60 seconds. Therefore:

3/5 * 1/2 * 1/2 * 60
= 3/5 * 1/2 * 30
= 3/5 * 15
= 9 seconds.

Answer: 2744 cm^3

A cube consists of six faces which are all squares. The formula for finding the area of a face of a cube (a square) is l^2 (or length squared). To find the length of one side of a square when the area is given, we find the square root of the area. The square root of 196 is 14.
Now, we can find the volume of the cube. The formula is V = l^3 (or length cubed). Therefore:
V = l^3
V = 14^3
V = 2744 cm^3.

Answer: Isosceles

To know the type of triangle, first you add all the angles given:
72+ 2y+ 1y = 180 (The angles of a triangle add up to 180 degrees)
72 + 3y = 180
3y= 180- 72
3y = 108
y = 108/3
y = 36
Now we know that the value of y is 36 degrees. The value of 2y will be 36*2 degrees, or 72 degrees. Therefore the angles of the triangle are 72 degrees, 72 degrees and 36 degrees. This tells us that the triangle is isosceles.

Answer: 5

A regular pentagon is a polygon with all its five sides and angles equal. And did you know that... a regular hexagon has 6 lines of symmetry, a regular heptagon has 7 lines of symmetry, a regular octagon has 8 lines of symmetry and so on? The number of sides the polygon consists of is equal to the number of lines of symmetry it has!

Answer: 0.0175 km

A regular heptagon has seven sides. If one side measures 2.5 m, then the perimeter of the heptagon (the distance around the heptagon) is 2.5 * 7 = 17.5 m = 17.5 / 1000 = 0.0175 km (1 km = 1000 m, therefore 1 m is 1/1000 of a kilometre). m^2 (metre squared) is a unit of area, not of perimeter.

Answer: 77 cm^3

If 1 litre = 1000 cm^3, then 1000 ml = 1000 cm^3 which means 1 ml = 1 cm^3. If Jill is given 11 millilitres of cough syrup every day for a week, she will drink 77 millilitres of cough syrup in a week (11*7; there are 7 days in a week). And as 1 ml = 1 cm^3, 77 ml = 77 cm^3!
I hope you enjoyed this quiz! If you have a problem with the above questions, don't hesitate to ask me. Mathematics is my favourite subject! :)