Final answer:
To make the expression equal to 4, use (2 + 1) * 2 = 4. To make the expression equal to 358, use 3 * (4 + 5) * 7 = 358.
Step-by-step explanation:
To make the expression equal to 4, parentheses could be placed as follows: (2 + 1) * 2 = 4. The expression inside the parentheses is evaluated first, with the addition resulting in 3. Then, 3 multiplied by 2 gives us the final answer of 4.
To make the expression equal to 358, parentheses could be placed as follows: 3 * (4 + 5) * 7 = 358. Again, the expression inside the parentheses is evaluated first, with the addition resulting in 9. Then, 3 multiplied by 9 gives us the final answer of 27. And finally, 27 multiplied by 7 gives us the desired answer of 189.