Option 2.
1. Simplify 7 + (12 - 9) + 7 × 3(8 - 5)
According to the Order of Operations, contents of parentheses are evaluated first. This gives
... 7 + 3 + 7 × 3 × 3
Then multiplication and division are performed left to right.
... = 7 + 3 + 21 × 3
... = 7 + 3 + 63
Followed by addition and subtraction left to right.
... = 10 + 63
... = 73
A Google search box can be relied upon to do the operations in the correct order.
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2. When the expression is rewritten, a different result is obtained. This is because the operations indicated by the second set of parentheses are altered.
... (7 + 12) - 9 + (7 × 3)8 - 5
... = 19 - 9 + 21 × 8 - 5
... = 19 - 9 + 168 - 5
... = 10 + 168 - 5
... = 178 - 5
... = 173
In the first expression, both +8 and -5 are multiplied by 21. In the rewritten expression, only +8 is multiplied by 21.
So you subtract their integers by starting from the bottom then coming up to the top. And you just put the numbers in your calculator. Once you’ve got your answer for X and Y, you multiply them both. Which will give you -9/3. Next you divide -9 by 3 and 3 divided by 3. Which will give you -3/1 and just rewrite it as -3. I don’t know if this helps but I hope it does :).
The train will pass the jogger in 36 seconds.
Length of train = 120m
Speed of train = 45kmph
Distance by which the jogger is ahead of the engine of the train = 240 m
Speed of jogger = 9 kmph
To pass the jogger, the train will have to cover the length of the train and the distance by which the jogger is ahead of the engine of train.
Hence,
Distance = 120 + 240 = 360m
As,
Time = Distance/Speed
Relative speed of train w.r.t jogger = 45 - 9 = 36 kmph = 10 m/s
Hence,
Time = 360/10 = 36 seconds.
To learn more about train, here:-
brainly.com/question/21218609
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