Solve the Parenthesis Conundrum for -36: Tips and Tricks

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To solve the expression 2 ⋅ 8 ÷ 4 - 20 to equal -36, the correct placement of parentheses is crucial. The successful solution is achieved by using the format 2 ⋅ [(8 ÷ 4) - 20], which simplifies to 2 ⋅ [-18] and results in -36. Initial attempts included various combinations but did not yield the desired result. The discussion highlights the importance of strategic parentheses placement in mathematical expressions. The final solution was confirmed and appreciated by the participants.
tionis
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Hi guys. I'm asked to insert parentheses where needed so that the following expression evaluates to the given number negative 36:

2 ⋅ 8 ÷ 4 - 20 = - 36

My attempts:

( 2 ⋅ 8 ) ÷ ( 4 - 20 ) = 16 ÷ -16 = -1

2 ⋅ ( 8 ÷ 4 ) - 20 = 2 ( 2 ) - 20 = -16

( 2 ⋅ 8 ÷ 4 ) - 20 = -16

I just don't know what other combination I can try that will yield -36 as a solution. Please help me. Thanks.
 
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Hint: 2 x -18 = -36

If you'll forgive the lack of parenthesis!
 
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PeroK said:
Hint: 2 x -18 = -36

If you'll forgive the lack of parenthesis!

I got it lol.

2 ⋅ [ ( 8 ÷ 4 ) - 20 ] = 2 [ ( 2 ) - 20 ]
= 2 [ -18] = -36

Thank you so much, PeroK! You're AWESOME!
 
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