Rebekah uses a balance scale to measure the weight of a rock in science class. She finds that its weight is 380 grams. If the actual weight is 363 grams, which of the following is closest to her percent error? Show how you made your choice.

the answer is 15% decrease

the barter

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116