Round off each of the following to the number of significant figures given in brackets.

(a) 289.0456 (4 s. 1)

(b) 1.236 (3 s. f.)

(c) * 0.06573 (2 s.)

(d) * 2408 (2 s. f.)

a) 289

b) 1.24

c) 0.066

d) 2400

Step-by-step explanation:

(a) 289.0456 (4 s. 1)

We want to round, 289.0456 to four significant figures.

We start counting from 2 because it is a significant digit and end on zero.

Therefore 289.0456=289.0 to 4 s. f

Or 289

(b) 1.236 (3 s. f.)

We want to round 1.236 to three significant figures.

We start counting from 1 and end on 3, but we need to run up because 6≥5

Therefore 1.236=1.24 to three significant figures.

(c) 0.06573 (2 s.)

To round 0.06573 to two significant figures, we need to start counting from the first non-zero digit, which is 6 and end on 5 and then round up because 7≥5

0.06573=0.066 to 2 s. f

(d) * 2408 (2 s. f.)

To round 2408 to two significant figures, we start counting from 2 and end on 4.

We round off because 0<5

In this case we need to replace all digits after 4 with zeros.

2408=2400 to 2 s. f