Question

name
phase
significant figures & scientific notation review 2 *

1. for the following numbers round to the correct significant figures

numbers round to three significant figures round to two significant figures
0.82778
900
20000
05846
3389.6
246.8
554.767

1. for the following placed the whole numbers placed into scientific notation (m.

x 10^n)
a) 8800
b) 0.57
c) 3350
d) 0.0376
e) 9.8
f) 0.00321

1. calculate the addition & subtraction with the correct no. of significant fi

Explanation:

Step1: Round 0.82778

Look at the fourth - digit for 3 significant figures. Since 7≥5, round up. For 2 significant figures, look at the third - digit. Since 7≥5, round up.
0.828 (3 significant figures), 0.83 (2 significant figures)

Step2: Round 900

For 3 significant figures, it is 900 (already has 1 significant figure, to get 3 we can write it as 9.00×10²). For 2 significant figures, it is 9.0×10².

Step3: Round 20000

For 3 significant figures, it is 2.00×10⁴. For 2 significant figures, it is 2.0×10⁴.

Step4: Round 5846 (assuming 05846 is just 5846)

For 3 significant figures, look at the fourth - digit. Since 6≥5, round up. For 2 significant figures, look at the third - digit. Since 4<5, round down.
5.85×10³ (3 significant figures), 5.8×10³ (2 significant figures)

Step5: Round 3389.6

For 3 significant figures, look at the fourth - digit. Since 9≥5, round up. For 2 significant figures, look at the third - digit. Since 8≥5, round up.
3.39×10³ (3 significant figures), 3.4×10³ (2 significant figures)

Step6: Round 246.8

For 3 significant figures, look at the fourth - digit. Since 8≥5, round up. For 2 significant figures, look at the third - digit. Since 6≥5, round up.
2.47×10² (3 significant figures), 2.5×10² (2 significant figures)

Step7: Round 554.767

For 3 significant figures, look at the fourth - digit. Since 7≥5, round up. For 2 significant figures, look at the third - digit. Since 4<5, round down.
5.55×10² (3 significant figures), 5.5×10² (2 significant figures)

Step8: Convert 8800 to scientific notation

Move the decimal point 3 places to the left. 8.80×10³

Step9: Convert 0.57 to scientific notation

Move the decimal point 1 place to the right. 5.7×10⁻¹

Step10: Convert 3350 to scientific notation

Move the decimal point 3 places to the left. 3.35×10³

Step11: Convert 0.0376 to scientific notation

Move the decimal point 2 places to the right. 3.76×10⁻²

Step12: Convert 9.8 to scientific notation

It is already in scientific notation as 9.8×10⁰

Step13: Convert 0.00321 to scientific notation

Move the decimal point 3 places to the right. 3.21×10⁻³

Answer:

Numbers	Round to three significant figures	Round to two significant figures
900	9.00×10²	9.0×10²
20000	2.00×10⁴	2.0×10⁴
5846	5.85×10³	5.8×10³
3389.6	3.39×10³	3.4×10³
246.8	2.47×10²	2.5×10²
554.767	5.55×10²	5.5×10²
8800 (scientific notation)	8.80×10³	-
0.57 (scientific notation)	5.7×10⁻¹	-
3350 (scientific notation)	3.35×10³	-
0.0376 (scientific notation)	3.76×10⁻²	-
9.8 (scientific notation)	9.8×10⁰	-
0.00321 (scientific notation)	3.21×10⁻³	-