Answer:
57.6
Explanation:
"Significant figures" refer to figures that have an actual contribution to a <em>number's value.</em>
They refer to all digits<u> except those with</u><em><u> </u></em><em><u>"leading zero,"</u></em> which means having a zero digit before a specific number. For example, in the number 0234, the significant figures are<em> 234. </em>
The rule for adding and subtracting significant figures is to <em>round off the answer to the least number of decimal places</em>. However, when it comes to multiplying and dividing significant figures, you have<em> round off the answer to the least number of significant digits.</em>
<u>Let's solve.</u>
21.4
+15
17.17
<u> 4.003</u>
57.573
Let's now round off to the<em> least number of decimal places</em>, which is the <em>tenths. </em>Since 0.5 is followed by a number greater than 5, we have to round it off to 6. Therefore, the answer is: 57.6
