Question

[ -15 ÷{ 5 of 8 ÷( 5 - 7 - 9 + 31 )}]× 3 of 3

Answer 1

The rules to follow:

1. work from the most inner bracket to the most outer
2. work on x and ÷ first (whichever is the leftmost) then work on + and - (whichever is the leftmost)

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[ -15 ÷ { 5 of 8 ÷( 5 - 7 - 9 + 31 ) } ] × 3 of 3

= [ -15 ÷ { 5 of 8 ÷( -2 - 9 + 31 ) } ] × 3 of 3

= [ -15 ÷ { 5 of 8 ÷( -11 + 31 ) } ] × 3 of 3

= [ -15 ÷ { 5 of 8 ÷ 20 } ] × 3 of 3

= [ -15 ÷ { 40 ÷ 20 } ] × 3 of 3

= [ -15 ÷ 2 ] × 3 of 3

= -7.5 × 3 of 3

= -22.5 x 3

= -67.5