11.

The mean of the median, mode and range of the observations 6, 6, 9, 14, 8, 9, 9, 8 is
 

• 10.3

• 8.5

• 10.5

• 8.8 

The expression x²-y²+x+y+2yz-z has one factor, which is 

• x+y-z+1

• x-y-z+1

• y-x+z

• x-y+z+1

In order to help the students with difficulties in remembering the geometrical terms and their meaning, a teacher must

• test students on definition of geometrical terms

• encourage group discussions

• stress on rote memorisation of all terms and definitions

• use lots of activities like preparing or solving crossword puzzles, jigsaw puzzles, etc

According to the given graph, between which two consecutive months was the change in the auto sales the greatest?

• April-May

• May-June

• January-February

• February-March

Two positive numbers x and y are inversely proportional. If x increases by 10%, then y decreases by

• $\frac{100}{11}$%

• $\frac{10}{11}$%

• 10%

• $\frac{2}{11}$%

How many lines of symmetry does a parallelogram have?

• None

• 4

• 3

• 2

The least number which is a perfect square and is also divisible by 10, 12, 15 and 18 is

• 1600

• 900

• 3600

• 2500

4-(2-9)⁰+3²$÷$1+3

• 15

• 12

• 17

• 16

In the figure, ABC is an isosceles triangle with CA = CB and BC is produced to a point D. If CE$\perp$BC, such that $\angle \mathrm{D}=\frac{1}{2}\angle \mathrm{E}=\frac{1}{2}\angle \mathrm{A}$ , then measure of $\angle$ACD is

• 135°

• 140°

• 110°

• 120°

The diameter of a cylindrical jar is increased by 25%. By what per cent must the height of the jar be decreased so that there is no change in its volume?

• 36

• 54

• 10

• 25