5/6 + 3/4= 8/10 what did they do wrong​

Tracy solved the following problem. which of the statements is true? 9 ÷ 3 + 6 × 2 3 + 6 × 2 9 × 2 18 her answer is correct. her answer is incorrect. she should have multiplied before dividing. her answer is incorrect. she should have multiplied before adding. her answer is incorrect. she should have added before dividing.

Which equation represents the partial sum of the geometric series?

Add the two expressions 3.8b - 7 and 2.9b + 9 enter your answer in simplified form