Answer:
He should have multiplied both numbers by 100
Step-by-step explanation:
Given
See Attachment for given
Required
What's Chen error
Chen error is at step 2 where he changed 0.9 to 9.
Any changes made on the divisor must also be made on the dividend
He got 9 by multiplying 0.9 by 10;
So, his mistake is that he should have multiplied both numbers by the same number.
From the list of given options, the option that best answer this question is He should have multiplied both numbers by 100
For this problem, I think there is no need for the details of 12 inches width and 4 inches length. This is because an equation is already given. It was clearly specified that A as a function of θ represents the area of the opening. Then, we are asked to find exactly that: the area of opening. Moreover, the value of θ was also given. Therefore, I am quite sure that the initial details given are for the purpose of red herring only.
So, all we have to do is substitute θ=45° to the function given.
A = 16 sin 45° ⋅ (cos 45° + 1)
The angle 45° is a special angle in trigonometry. So, it would be easy to remember trigonometric functions of this angle. Sine of 45° is equal to √2/2 while cosine of 45° is also √2/2.
A = 16(√2/2) ⋅ (√2/2 + 1)
A = 8+8√2
A = 19.31 square inches
Y is already solved because y=kt
Multiply 2.25 by each answer and 750 and write down the total next multiply 3.25 by each answer lowest to highest once you get a product that is higher than you writen down answer play around with the numbers until you get the exact amount D 760 2.25 times 760 is 2460 by 3.25 its 2570 you save 10 dalloars and are able to pay for the food and band