MATHEMATICS FORM 1 – UNITS

UNITS OF LENGTH

Basic unit of length is meter.

Other unit are such as :-

Km hm dam m dm cm mm

1 0 0 0 0 0 0

1 0 0 0 0 0

1 0 0 0 0

1 0 0 0

1 0 0

1 0

1

EXAMPLES

1. Convert 9.17m into km

2. Convert 2/51km into :-

(a) dm (b) mm (c) hm(A)

(a)

(b)

OPERATIONS ON UNIT OF LENGTH

1. Addition

Example Add the following:-

Question

1. Add together the following length (a) 785m, 97m, 605m, (b) 8dam, 9m, 2cm (Give your answer in metre.

Solution

Add

SUBSTRATION
EXAMPLE

perform the following

MULTIPLICATION
EXAMPLES

DIVISION

Perform the following meter.

EXAMPLE

2. Evaluate 38m ÷ 50 = (Give your answer in centimeter).

3. Find the following in meter

EXERCISE

2. A roil of string ps 8.3 metres long. pieces of string of length 2.30m, 78m, 2.37m and 0.95m are cut off. The remaining part is divided into equal pieces of length 32cm. How many equal pieces are there?

There are 19 pieces.

OPERATION ON UNITS OF MASS

EXAMPLE

60 seconds = 1 minutes

60 minutes = 1 hour

24 hour = 1 day

7 days = 1 week

4 week = 1 month

28, 29, 30 or 31 days = 1 month

12 month = 1 year

365 or 366 days = 1 year

365 or 36 days = 1 year

Time can be measured by using a clock.

There are two ways of reading time clock :-

(i) By reading time in 12 hours

(ii) By reading time in 24 hours.

EXAMPLES

1. Change 25 minutes past 10 in the following using :-

(a) 12 hours clock

(b) 24 hours closk

Solution:

(a) 12 hours clock

10:25am

(b) 24 hours clock

10:25 hours

2. Write the following times using a 24 – hours clock :

(a) 6: 30 am

(b) 9: 45 p.m

. Solution:

(a) 6:30 a.m it will be in 24 hours is 0630 hours

(b) 9:45 p.m it will be in 24 hours is 2145 hours.

3. Write the following times in words using 12 hours clock :-

(a) 2040

(b) 2349

Solution :

(a) 08:40 p.m

It is forty minutes past eight. Twenty minutes to nine.

(b) 11:49 pm

It is four nine minutes past eleven .

Eleven minutes to twelve

3. Write the following times using a 24 hours clock.

(a) 3:20p.m

(b) 5:37 p.m

(c) 70:53 a.m

Solution

(a) 1520 hours

(b) 1737 hours

(c) 0453 hours

UNIT OF CAPACITY

The basic unit is litre (l)

Other unit are:

NOTE:

1l = 1000cm3

1k = 10000l

1? = 1000ml

Conversion of unit of capacity

EXAMPLES

Change the following into cm3:-

(a) 6.5 litre

(b) 35 litre

EXERCISE

1. One litre of cooking oil cost sh. 700. Find the cost of 15 litres

Solution:

Sh. 700 x 15 litres

= Tsh 10,500

2. Doto sells 1 litre of milk for sh. 100. How many litres of milk should Doto sell to get sh. 34,800?