## Wednesday, June 8, 2011

### June Vacation Chap 9.2 RATE (L4) Self-Paced Learning

1. Mathematics Textbook 1B
(a) Go through Chapter 9 (p9 to p11)
(b) Attempt Exercise 9.2 Q1 to Q10.

2. ACELearning Portal: eLearning Portal
> Subject: Secondary 1 Express
> Ratio, Rate and Speed: Choose Rate

(a) Go through video lessons: Rate, Average Rate, Example 1, Example 2
Note: An email has been sent to all students via the AceLearning

1. This comment has been removed by the author.

2. This comment has been removed by the author.

3. 1a. \$3.50/ℓ
1b. 72 vases/day
1c. 47 words/min
1d. \$80/m2
1e. 4 kg/m
1f. 60 g/egg

2a. \$23/h
2b. \$920/week

3a. 9 km/ℓ
3b. \$1.20/ℓ

4a. 87.5 g/cubes
4b. 4.2 g/cm2

5a. \$15/ticket
5b. \$150

6a. \$22.50/m2
6b. \$450

7a. 27 ℓ/min
7b. 3 min

8a. \$26/kg
8b. 25g
8c. 3000g, \$78

9a. \$201.60
9b. \$4200/m2

10a. 19.3 g/cm3
10b. No, it is not. A pure gold cube of that measurement should weigh 154.4g, instead of 120g.

4. 1a: \$3.5/ℓ
1b: 72 vases/day
1c: 47 words/min
1d: \$80/ mˆ2
1e: 4 kg/m
1f: 60 g/egg

2a: \$24 hourly
2b: \$920 weekly

3a: 9km/ℓ
3b: \$1.20/ℓ

4a: 87.5 g/ cubes
4b: 4.2 g/ cmˆ3

5a: \$15/ ticket
5b: \$150

6a: \$22.50/mˆ2
6b: \$450

7a: 27ℓ/min
7b: 3min

8a: \$26/kg
8b: 25g
8c: 3000g (Mass), \$78 (Cost)

9a: \$201600
9b: \$4200/mˆ2

10a: 19.3 g/cmˆ3
10b: It is not made of pure gold because its mass is 120g, while the pure gold cube of the same size has a mass of 154.4g.

5. 1a. \$3.50/ℓ
1b. 72 vases/day
1c. 47 words/min
1d. \$80/m2
1e. 4 kg/m
1f. 60 g/egg

2a. \$23/h
2b. \$920/week

3a. 9 km/ℓ
3b. \$1.20/ℓ

4a. 87.5 g/cubes
4b. 4.2 g/cm2

5a. \$15/ticket
5b. \$150

6a. \$22.50/m2
6b. \$450

7a. 27 ℓ/min
7b. 3 min

8a. \$26/kg
8b. 25g
8c. 3000g, \$78

9a. \$201.60
9b. \$4200/m^2

10a. 19.3 g/cm^3
10b. No. A pure gold cube would weigh 154.4g, but the cube weighed 120g only.

6. 1a)\$3.5/ℓ
b)72 vases/day

c)47 words/min

d)\$80/m^2

e)0.25 kg/m

f)60g/egg

2a)\$4.6/hour
b)\$257.6/hour

3a)9km/ℓ
b)\$1.4/ℓ

4a)87.5 /cube
b)0.343/cm^3

5a)\$15/ticket
b)\$150

6a)\$22.5/m^2
b)\$450
7a)27ℓ/min
b)3min

8a)\$26/kg
b) 25g
c)3000g
\$78

9a)\$201600’
b)\$4200/m^2

10a)19.3 g/cmˆ3

7. 1a. \$3.50/ℓ
1b. 72 vases/day
1c. 47 words/min
1d. \$80/m²
1e. 4 kg/m
1f. 60 g/egg

2a. \$23/h
2b. \$920/week

3a. 9 km/ℓ
3b. \$1.2/ℓ

4a. 87.5 g/cube
4b. 4.2 g/cm³

5a. \$15/ticket
5b. \$150

6a. \$22.50/m²
6b. \$450

7a. 27 ℓ/min
7b. 3 min

8a. \$26/kg
8b. 25 g
8c. Mass: 3000 g, Cost: \$78

9a. \$201 600
9b. \$4200/m²

10a. 19.3 g/cm³
10b. No. A pure gold cube of the same size (Which is of side 2 cm) would have a mass of 154.4g instead of 120 g.

8. 1. (a) \$3.5/ℓ (b) 72vase/day
(c) 47words/min (d) \$80/m*2
(e) 4kg/m (f) 60g/egg

2. (a) \$23/h (b) \$920/week

3. (a) 9km/litre (b) \$1.2/litre

4. (a) 87.5g/cube (c) 4.2g/cm*3

5. (a) \$15/ticket (b) \$150

6. (a) \$22.50/m*2 (b) \$450

7. (a) 27ℓ/min (b) 3min

8. (a) \$26/kg (b) 25g/m*2
(c) cost:\$78 mass:3000g

9. (a) \$201600 (b) \$4200/m*2

10. (a) 19.3g/cm*3

(b) No. If u measure the weight of a pure gold cube with the the rate i have just found and compare between the 2 cubes and u will find that they are not the same. the real one is not as heavy as a pure gold cube so it is no pure gold.
pure:154.4 not pure gold: 120g

9. 1a. \$3.50/ℓ
1b.72vases/day
1c.47words/min
1d.\$80/m*2
1e.4kg/m
1f.60/egg

2a.\$23/h
2b.\$900/week

3a.9km/ℓ
3b.1.2/ℓ

4a.87.5g/cube
4b.2g/cm*2

5a.\$15/ticket
5b.\$150

6a.22.50/m*2
6b.\$450

7a.27ℓ/min
7b.3min

8a.\$26/kg
8b.25g/m*2
8c(a)\$78
(b)300g

9a.\$201600
9b.\$4200/m*2

10a.19.3g/cm*3
10b.No.As the difference of 1cm on each side of the pure gold cube would not cause to have a difference of 401.1g, therefore it is not pure gold.

10. 1a . \$3.50/ℓ
1b . 72 vases / day
1c . 47 words / min
1d . \$80 / m²
1e . 4kg / m
1f . 60g / egg

2a . \$23 / h
2b . \$920 / week

3a . 9 km /ℓ
3b . \$1.20 /ℓ

4a . 87.5g / cube
4b . 4.2g / cm³

5a . \$15 / ticket
5b . \$150

6a . \$22.50 / m²
6b . \$450

7a . 27ℓ/ min
7b . 3 minutes

8a . \$26 / kg
8b . 25g
8c . Mass : 3000g
Cost : \$78

9a . \$201600
9b . \$4200 / m²

10a . 19.3g / cm³
10b . No. That cube has a volume of 8cm³ , which should have a mass of 154.4g if it was made of pure gold . But it's mass is 120g which means the cube is not made of pure gold.

11. 1. (a)
\$7÷2ℓ=\$3.50
Ans:\$3.50/ℓ

(b)
360÷5=72
Ans:72 Vases/Day

(c)
376÷8=47
Ans:47 words/min

(d)
\$240÷3m²=\$80
Ans:\$80/m²

(e)
10kg÷2.5m=4kg
Ans:4kg/m

(f)
720g÷12 eggs=60g
Ans:60g/egg

2. (a)
\$184÷8 hours=\$23
Ans:\$23/hr

(b)
\$184x5 days=\$920
Ans:\$920/week

3. (a)
225km÷25ℓ=9km
Ans:9km/ℓ

(b)
\$30÷25ℓ=\$1.20
Ans:\$1.20/ℓ

4. (a)
525g÷6 Cubes=87.5g
Ans:87.5g/cube

(b)
5³cm=125cm³
525g÷125cm³=4.2g
Ans:4.2g/cm³

5. (a)
\$120÷8 Tickets=\$15
Ans:\$15/ticket

(b)
\$15x 10 Tickets= \$150
Ans:\$150

6. (a)
\$270÷12m²=\$22.50
Ans:\$22.50/m²

(b)
\$22.50x20=\$450
Ans:\$450

7. (a)
20 sec x 3= 1 min
9ℓx3=27ℓ
Ans:27ℓ/min

(b)
Length(60cm) x Breadth(45cm) x Height(30cm) = 81000cm³
1ℓ=1000cm³
9ℓ=9000cm³
81000cm³÷9000cm³=9
20sec x 9=180sec
180sec=3min
Ans:3 min

8. (a)
500g x 2= 1000g
= 1kg
\$13x2=\$26
Ans:\$26

(b)
500g÷20m²=25g
Ans:25g/m²

(c)
15m x 8m= 120m²
120m²÷20m²=6
500g x 6= 3000g
= 3kg
\$13 x 6= \$78
Ans: Cost: \$78
Mass: 3kg

9. (a)
Jenny(2 units)
Mother(3 units)
\$504000÷5=\$100800
\$100800 x 2= \$201600
Ans: \$201600

(b)
\$504000÷120m²=\$4200
Ans:\$4200/m²

10. (a)
3³cm=27cm³
521.1g÷27cm³=19.3g
Ans:19.3g/cm³

(b)
2³cm= 8cm³
19.3g x 8= 154.4g
No, it is not made up of pure gold. As its volume is only 8cm³ the
mass is supposed to be 154.4g, instead of 120g. Therefore it is
not pure gold.

12. 1a) \$7/2L=\$3.50/L
Ans:\$3.50/L
1b) 360 vases/5 days=72 vases/day
Ans:72 Vases/Day
1c) 376/8=47 words/min
Ans:47 words/min
1d) \$240/3m²=\$80/m²
Ans:\$80/m²
1e) 10kg/2.5m=4kg/m
Ans:4kg/m
1f) 720g/12 eggs=60g/egg
Ans:60g/egg

2a) \$184/8 h=\$23/h
Ans:\$23/h
2b) \$184x5 days=\$920/week
Ans:\$920/week

3a) 225km/25L=9km/L
Ans:9km/L
3b) \$30/25L=\$1.20/L
Ans:\$1.20/L

4a) 525g/6 Cubes=87.5g/L
Ans:87.5g/cube
4b)5³cm=125cm³
525g/125cm³=4.2g/cm³
Ans:4.2g/cm³

5a) \$120/8 tickets=\$15/ticket
Ans:\$15/ticket
5b) \$15x 10 tickets= \$150
Ans:\$150

6a) \$270/12m²=\$22.50/m²
Ans:\$22.50/m²
6b) \$22.50x20=\$450
Ans:\$450

7a) 1 min=60sec
60/20=3
9L x3=27L
Ans:27L/min
7b) Length(60cm) x Breadth(45cm) x Height(30cm) = 81000cm³
27L=27000cm³
81000cm³/27000cm³=3 min
Ans:3 min

8a) 1kg=1000g
1000g/500g=2
\$13x2=\$26
Ans:\$26
8b) 500g/20m²=25g
Ans:25g
8c) 15m x 8m= 120m²
120m²/20m²=6
Mass: 500g x 6= 3000g
= 3kg
Cost: \$13 x 6
= \$78
Ans: Cost: \$78
Mass: 3kg

9a)\$504000/5=\$100800
\$100800 x 2= \$201600
Ans: \$201600
9b) \$504000÷120m²=\$4200
Ans:\$4200/m²

10a) 3³cm=27cm³
521.1g/27cm³=19.3g
Ans:19.3g/cm³
10b)2³cm= 8cm³
19.3g x 8= 154.4g
No, it is not made up of pure gold.The mass of a pure gold cube of
side 2cm should be 154.4 grams instead of 120g

13. Practice 9.2
1.

a) \$3.50/L
b) 72 vases/day
c)47 words/min
d)\$80/m^2
e)4kg/m
f)6g/egg

2.
a) \$23
b)\$15

3.
a)9km/L
b)\$1.20/L

4.
a)87.5g/cube
b)125cm^3/cube

5.
a)\$15/ticket
b)\$150

6.
a)\$22.50/m^2
b)\$450

7.
a)27L/min
b) 180 s

8.
a)\$26/kg
b)25g
c)3kg,\$78

9.
a)\$201600
b)\$4200/m2

10.
a)19.3g/cm^3
b) No. It is because when a pure gold cube of side 3cm is changed to 2cm the the mass is different from the other cube

14. 1.
a) \$3.50/L
b) 72 vases/day
c) 47 words/min
d) \$80/m²
e) 4kg/m
f) 60g/egg

2.
a) \$23/h
b) \$115/week

3.
a) 9 km/L
b) \$1.20/L

4.
a) 87.5g/cube
b) 4.2g/cm³

5.
a) \$15/ticket
b) \$150/10 tickets

6.
a) \$22.5/m²
b) \$450/20 floor tiles

7.
a) 27L/min
b) 27L/min

8.
a) \$26/kg
b) 25g
c) 3kg, \$78

9.
a) \$403200
b) \$4200/m²

10.
a) 19.3g/cm³
b) No. 1 cm³ of the 3 cm by 3 cm by 3 cm gold has a weight of 19.3g but 1 cm³ of the 2 cm by 2 cm by 2 cm has a weight of 15g. So the other cube of gold is not fully made up of gold.