Justine tried to evaluate an expression. Here is her work:10−4+2(4)210−4+82 {Step 1}10−4+64 {Step 2}6+64 {Step 3}70 {Step 4}Is Justine's work correct?Choices:(A)No, Justine made a mistake going from the given expression to Step 1. Justine should have squared 4 before multiplying. The order of operations says to evaluate exponents before you multiply.(B)No, Justine made a mistake going from Step 2 to Step 3. Justine should have added before she subtracted. The order of operations says to add before you subtract.(C)Yes, Justine's work is correct.
Q. Justine tried to evaluate an expression. Here is her work:10−4+2(4)210−4+82 {Step 1}10−4+64 {Step 2}6+64 {Step 3}70 {Step 4}Is Justine's work correct?Choices:(A)No, Justine made a mistake going from the given expression to Step 1. Justine should have squared 4 before multiplying. The order of operations says to evaluate exponents before you multiply.(B)No, Justine made a mistake going from Step 2 to Step 3. Justine should have added before she subtracted. The order of operations says to add before you subtract.(C)Yes, Justine's work is correct.
Handle Exponent First: Justine starts with the expression 10−4+2(4)2. According to the order of operations, we should handle the exponent first. Justine should calculate (4)2 before multiplying by 2.
Correct Next Step: Justine then writes 10−4+82. This is incorrect because she should have written 10−4+2×16, as (4)2 equals 16, not 8. The correct next step should be 10−4+32.
More problems from Interpret confidence intervals for population means