Number Ninjas
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100

18×25

450

100

Find the complement of 27°

63°

100

Name the triangle with side lengths:

6 cm, 6 cm, 9 cm.

Isosceles

100

3x+8=26

x=6

200

52+33

25 + 27 = 52

200

Two supplementary angles differ by 24°.

Find both angles.

Let the angles be x and x+24

x+x+24=180

2x=156

x=78

Angles are

78° and 102°

200

Which measure of centre is usually closest to the long tail in a positively skewed graph?

A) Mode

B) Median

C) Mean

Mean

200

A jumper costs $120.

It is discounted by 15%.

How much is the discount?

15% of 120

= $18

300

A number is divisible by both 6 and 9. Name the smallest possible positive number.

18

300

An angle at a point is made up of:

95°, 68°, x° and 104°.

Find x.

95+68+104=267

360−267=93°

300

Name the quadrilateral.

  • Opposite sides parallel
  • Four right angles
  • Opposite sides equal

Rectangle

300

A class of 25 students was surveyed.

16 students preferred basketball.

What percentage preferred basketball?

16÷25×100

= 64%

400

−42+32

Remember powers before negatives.

−42=−(42)=−16

32=9

−16+9=−7

400

Two parallel lines are cut by a transversal.

One angle measures 124°.

Find:

  • the corresponding angle
  • the alternate angle
  • the co-interior angle.

Corresponding = 124°

Alternate = 124°

Co-interior = 56°

400

Which quadrilateral has

  • four equal sides
  • opposite angles equal
  • diagonals meet at right angles

but does not have to contain right angles?

Rhombus

400

A rectangle has an area of 96 cm².

Its width is 8 cm.

Find its perimeter.

Length

96÷8=12

Perimeter

2(12+8)

= 40 cm

500

(−3)3+42

(−3)3=−27 

42=16

−27+16=−11

 

500

Two parallel lines are cut by a transversal.

One angle is 68°.

Another angle x is vertically opposite to the corresponding angle.

Find x.

Corresponding = 68°

Vertically opposite = 68°

Answer: 68°

500

 triangle has angles

48°, 48° and 84°.

Classify it by:

  • sides
  • angles

Sides:

Isosceles

Angles:

Acute

500

A tank contains 240 L of water.

Every minute 18 L is removed.

How much water remains after 7 minutes?

18 × 7 = 126

240 −126

= 114 L