You haven't provided expressions, so I can work out the problem for you. When we divide fractions, remember always "keep, switch, flip!" That's what we're gonna do here. We keep the 2/5, switch the sign to multiplication, and flip the 7/8 to 8/7. Therefore, we have 2/5*8/7. That gives us 16/35. Hope this helps!
Answer: tan 1 radians = 1.557, tan 1 degrees = 0.017
For number 9, you know that it makes 40 copies every five minutes. All you have to do is divide 40 by 5.
40 ÷ 5 = 8
It makes 8 copies every minute.
Your chart can also help you check your answer. It says that it makes 96 copies every 12 minutes and it makes 104 copies every 13 minutes. So multiply 8 by 12 to check it and 8 by 13.
8 • 12 = 96
8 • 13 = 104
Since those answers match up with the chart, it must be correct.
The photocopier makes 8 copies every minute. Hope that helps!
For the average to be 90,
(99 + 93 + x) / 3 = 90
or 192 + x = 270
or x = 270 - 192 = 78
Jim must score at least 78 in the third test.