Question

write the value of (11.2)²-(0.375 ÷3)
iexactly
ii.to two significant figures
iii.in standard farm

Answer 1

Given:  (11.2)² - (0.375 ÷ 3)

To find:

i) exact answer

ii) to two significant figures

iii) in standard form

Solution:

(11.2)² - (0.375 ÷ 3)

= 125.44 - (0.375 ÷ 3)

= 125.44 - 0.125

= 125.315

i) Exact answer= 125.315

ii) Rounded to two significant figures= 12

iii) In standard form= 1.25315 × 10²

Answers: i) The exact answer is 125.315.

               ii) The answer that is rounded off to two significant figures is 12.

               iii) The answer in the standard form is 1.25315 × 10².

Answer 2

Exact Value of of (11.2)²-(0.375 ÷3) is 125.315

130 is to the  two significant figures

1.25315 × 10² in standard form / scientific notation

Given:

• (11.2)²-(0.375 ÷3)

To Find:

• Value
• i   exactly
• ii  two significant figures
• iii  in standard farm

Solution:

Significant figures / digits

• All non-zero digits are significant.
• The leftmost nonzero digit is the first or most significant figure.
• If there is a decimal point, the rightmost digit is the last or least significant figure
• If there is no decimal point explicitly shown, the rightmost non-zero digit is the least significant figure
• All digits between the most significant figure and the least significant figure are significant.

Scientific notation or Standard form  

• Very large and very small numbers can be expressed in standard form.
• Standard form is also called scientific notation form
• It is written in the form of c × 10ⁿ where  c > 1, c < 10, and n is an integer.  

Step 1:

Solve first 0.375 ÷3

(11.2)²-(0.125)

Step 2:

Calculate  (11.2)² and remove parenthesis

125.44- 0.125

Step 3:

Perform subtraction

125.315

Exact Value is  125.315

Step 4:

Round off to 2 significant figures

130

Step 5:

write 125.315 in standard form / scientific notation

1.25315 × 10²