Ascale has a percent error of 5% the actual mass of a rock is 258g

this scale is likely to show the mass of either

245.1 253.0 256.7 257.5 g or 259.3 259.5 263.0 270.9 g.

, pick them wisely, you can pick one for each side. and remember it's not percent its percent error

245.1 g or 270.9 g

Step-by-step explanation:

Error in mass for the measurement is 5% of the actual mass . This simply means 5% of 258 grams. Mathematically,

error in mass = percentage error × actual mass

error in mass = 5 /100 × 258

error in mass = 1290/100

error in mass = 12.90 grams

Since the error in mass is 12.90 grams that means the scaled mass either has an increase of 12.9 g or decrease of 12.9 g from the actual mass.

scaled mass can be either 258 - 12.90 = 245.1 grams

or

258 + 12.90 = 270.9 grams

the first option is the answer.