Question

1. \\(\frac{1}{2}50 - (20 + 8)\\)\

what do the parentheses indicate in this expression?\
\\(\boldsymbol{a}\\). subtract 20 from 50 before adding 8.\
\\(\boldsymbol{b}\\). multiply \\(\frac{1}{2}\\) by 50 then subtract 20 + 8.\
\\(\boldsymbol{c}\\). add 20 and 8 before subtracting from 50.\

1. evaluate.\

\\(54 + (7 - 4)\\)

Explanation:

Question 4

Step1: Analyze the expression $\frac{1}{2}[50 - (20 + 8)]$

The parentheses around $(20 + 8)$ mean we perform the addition of 20 and 8 first, then subtract that result from 50, and finally multiply by $\frac{1}{2}$. Let's check the options:

• Option a: Says "Subtract 20 from 50 before adding 8" – but the parentheses are around 20 + 8, so we add first, not subtract 20 from 50 first. So a is wrong.
• Option b: Says "Multiply $\frac{1}{2}$ by 50 then subtract 20 + 8" – the order here is multiply first, but the parentheses are about the addition inside the subtraction. The correct order from parentheses is add 20 and 8 first, then subtract from 50, then multiply by $\frac{1}{2}$. But let's check option c.
• Option c: Says "Add 20 and 8 before subtracting from 50" – the parentheses around $(20 + 8)$ indicate that we add 20 and 8 first, then subtract that sum (28) from 50 (so 50 - 28), and then multiply by $\frac{1}{2}$. So this matches the order of operations (PEMDAS/BODMAS: parentheses first, then subtraction inside the brackets, then multiplication). So option c is correct.

Step1: Evaluate the innermost parentheses first: $(7 - 4)$

$7 - 4 = 3$

Step2: Now evaluate the next parentheses: $[4 + (7 - 4)] = [4 + 3]$

$4 + 3 = 7$

Step3: Finally, multiply by 5: $5[4 + (7 - 4)] = 5\times7$

$5\times7 = 35$

Answer:

c. Add 20 and 8 before subtracting from 50.

Question 5