Question

Find the value of the expression to access gate D:

$9+\left\{\right[(4\times 4)+(15÷3)]\times 1\}-10+9-6+7÷1$

• A. 20
• B. 30
• C. 40

Answer 1

The correct option is B 30

We solve the expression inside the parenthesis first as per the PEMDAS rule.

As there are many parentheses in the given expression, we solve the expression with innermost parentheses first.

$9+\left\{\right[(4\times 4)+(15÷3)]\times 1\}-10+9-6+7÷1$
$=9+\left\{\right[16+(15÷3)]\times 1\}-10+9-6+7÷1$
$=9+\left\{\right[16+5]\times 1\}-10+9-6+7÷1$

Now let's solve the expression inside the square brackets.

$9+\left\{\right[16+5]\times 1\}-10+9-6+7÷1$
$=9+\{21\times 1\}-10+9-6+7÷1$

Now, solve the expression inside the curly brackets.

$=9+21-10+9-6+7÷1$

Now, we solve the division operation.

$=9+21-10+9-6+7$

Finally, we solve the addition and subtraction operations, starting from left to right.

$=30-10+9-6+7$
$=20+9-6+7$
$=23+7$
$=30$

$\therefore$ The value of the expression is $30.$