HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 1 - STARTERS (INDIVIDUAL)

Marks: 2 marks to either or both competitors for the correct answer

Time: 30 seconds.

Year

13 1) An arithmetic series has first term 6 and the sum of its
first 30 terms is 615. Find the second term.

12 2) Express the recurring decimal as a fraction in its lowest terms.

10-11 3) Express as a recurring decimal.

7-9 4) Express as a fraction in its lowest terms

13 5) Find a given that

12 6) A model of a building has scale factor 1:50. If the floor area
of the building is 1700m2 find, in m2, correct to one significant
figure, the floor area of the model.

10-11 7) Find the largest prime factor of 2010.

7-9 8) Find the area of a triangle with sides 6cm, 8cm and 10cm.

HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 2 - GEOMETRY AND TRIGONOMETRY (PAIRS)

Marks: 2 marks to either or both pairs for the correct answer

Time: 90 seconds.

All the questions in this section refer to the cube ABCDEFGH of side 3cm.

Each of the points marked on the edges is 1 cm from a vertex.

Year

7-11 1) Find the area of rectangle LMNQ.

12-13 2) Find the area of rectangle LQTS.

7-11 3) Find the area of rectangle PQRS.

12-13 4) Find the area of trapezium PQFG.

HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 3 - MENTAL ARITHMETIC AND PROBABILITY (INDIVIDUAL)

Marks: 2 or 1 to opponent

Time: 60 seconds

All questions are to be done mentally

Body Mass Index (BMI) =

Year

7-9 1) Find the BMI of Alf who is 2 m tall and has mass 80 kg.

2) Find the BMI of Bess who is 1.2 m tall and has mass 36 kg.

10-11 3) Find the mass of Ernie who is 1.5 m tall and has a BMI of 24.

4) Find, to the nearest kg, the mass of Flo who is 1.4 m tall
and has a BMI of 20.

12 5) Find, to the nearest 10cm, the height in centimetres of Chris who has mass 60 kg and has a BMI of 20.

6) Find, to the nearest 10cm, the height in centimetres of Doug who has mass 82 kg and has a BMI of 25.

13 7) Find, to the nearest kg, the mass of the tallest man.
He was 2.7m tall and had a BMI of 30.

8) Find, to the nearest kg, the mass of the tallest woman.
She was 2.2m tall and had a BMI of 30.


HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 4 - TEAM QUESTION

Time: 5 minutes.

P(n) is defined as the product of the digits of the positive integer n.

For example: P(469) = 4 × 6 × 9 = 216

P(464) = 4 × 6 × 4 = 96 .

Find as many positive integers n as you can where n < 400 and

P(n) has a last (units) digit of 6.

You will be given 5 minutes for working. Then the Team Captain will be given some extra time to compile a single list of answers.

Marks:

1 point for each correct answer, -1 for each incorrect answer.

Each team receives their Total Points Score ÷ 10, rounded to the nearest integer (half rounds up), with minimum score zero.

Answers:

6, 16, 23, 28, 32, 44, 49, 61, 66, 78, 82, 87, 94,

116, 123, 128, 132, 144, 149, 161, 166, 178, 182, 187, 194,

213, 229, 231, 247, 268, 274, 279, 286, 292, 297,

312, 321, 326, 334, 343, 348, 362, 367, 376, 384, 389, 398

(47 solutions)

HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 5 - CALCULATORS (INDIVIDUAL)

Marks: 2 to either or both competitors for the correct answer

Time: 90 seconds

You are reminded that the written questions are to be given simultaneously to the respective pupils at the beginning of this section.

Year

7-9 1) Find, to the nearest 100, the sum of the first 7 terms of
the series

.

10-11 2) Find, correct to 2 significant figures, the sum of the first 12 terms
of the series

.

12 3) The sum of the infinite series is 1.

When the first 12 terms are added the sum is .

Find k correct to 2 significant figures.

13 4) The first three terms of a series for are given here: .

Use the first four terms to find an approximate value of .

Give your answer correct to 5 decimal places.


HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 6 - ALGEBRA AND CALCULUS (INDIVIDUAL)

Marks: 2 or 1 for opponent

Time: 60 seconds.

Throughout this section the operation * is defined by

a * b = (a + b)(a2 – ab + b2) .

Example: 3 * 2 = (3 + 2)(32 – 3 × 2 + 22) = 5 × (9 – 6 + 4) = 35.

Year

7-9 1) Find the value of 4 * 2.

2) Find the value of 3 * 5 .

10-11 3) Find the value of (1 * 2) * 3 .

4) Find the value of (2 * (-1)) * ((-2) * 1) .

12 5) Given that (2x) * x = 1125, find the value of x .

6) Given that (4x) * (3x) + (2x) * 1 = 100, find the value of x.

13 ) Find [(2x)*)] .

8) Find .


HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

SECTION 7 - RACE (INDIVIDUAL)

Marks: 2 or 0

Time: 60 seconds.

Year

7-9 1) Find the two prime numbers with a sum of 100 and the largest difference.

10-11 2) Find the two prime numbers with a sum of 100 and the smallest difference.

12 3) Given that + 2 = a , find the value of a .

13 4) Solve

7-9 5) Find the number of degrees through which the hour hand
of a clock turns in 24 hours.

10-11 6) Find the number of triangular tiles shown below needed
to cover a square of side 48cm.

12 7) Find the area under the line between the lines

, and the x axis.

13 8) Find the value of sin 2010º .


HANS WOYDA MATHEMATICS QUIZ COMPETITION 2010/2011

ROUND 2

ANSWERS (allow equivalent answers except where stated)

SECTION 1

1. 7

2. 41/333 (must be in lowest terms)

3.

4. 1/81

5. 80

6. 0.7 (m2)

7. 67

8. 24 (cm2)

SECTION 2

1. 4 (cm2)

2. (cm2)

3. 3 (cm2)

4. 6 (cm2)

SECTION 3

1. 20

2. 25

3. 54 (kg)

4. 39 (kg)

5. 170 (cm)

6. 180 (cm)

7. 219 (kg)

8. 145 (kg)

SECTION 4

Please see separate answer sheet

SECTION 5

1. 779800

2. 9.0 (must be 2 S.F.)

3. 0.00024

4. 3.14085

SECTION 6

1. 72

2. 152

3. 756

4. 0

5. 5

6. 1

7. 24x2 + 6x5

8. (+ c)

SECTION 7

1. 3, 97

2. 47, 53

3. 3

4. 2

5. 720 (º)

6. 384

7. 25.5

8. -½