Interhouse Mental Maths Final

beginner 1

100

(9x7) + (4x16)

127

200

The volume of a cuboid is 140cm³ and its height and width are 7 cm and 5cm respectively. Find its length

length= 4cm

300

2x-5 =13-4x, find for x

x=3

400

The ratio of cats to dogs is 3 : 5.
If there are 15 cats, how many dogs are there?

25 dogs

500

4a+b-3b+5a, simplify this

9a-2b

beginner 2

100

Round 3.478 to 2 decimal places.

3.48

200

A bag contains red, blue, and green marbles in the ratio 3 : 2 : 5.
If there are 20 marbles altogether, how many are blue?

4 blue marbles

300

Find the area of a triangle with base 10 cm and height 6 cm.

30cm²

400

5³+6²+39

200

500

One angle of a triangle is 45° and another is 65°.
Find the third angle.

70 degrees

Intermediate 1

100

factorize completely x²−9x+20 

 (x-4)(x-5)

200

x²+5x−14=0 , solve for x

x=-7 ,x=2

300

Find the equation of the line with gradient −2 passing through (4,−1)

y=-2x + 7

400

The sum of two consecutive integers is 47.
Find the integers.

23 and 24

500

(3⁴÷3²)×3

27

Intermediate 2

100

Find the midpoint of the line joining(−2,5) and (4,−1)

(1,2)

200

Find the surface area of a cube of side 6 cm.

216cm²

300

A shirt marked $400 is sold at a 15% discount.
Find the selling price.

$340

400

A rectangular tank measures 2 m by 1.5 m by 1 m.
Find the volume of water it can hold in litres. 

note:1m³=1000 litres

3000litres

500

State Cosine Rule formula

a²= b²+c²-2bcCos(a)

Senior 1

100

what are the nature of the roots of x²+3x+7

Complex

200

how would one determine the stationary points of f(x) and their nature.

find f^'(x), solve/let it equal 0 and find for x

substitute the values of x into f(x) to find y

find f"(x) and plug in the values of x

if +ve: minimum if -ve: maximum

300

What is the formula for the Sum to infinity of a Geometric series

S_inf =  a / 1-r 

400

The Cosine of the angle between 2 perpendicular vectors is?

0

500

log₂(x) = 5

x=32