Answer:
C
Step-by-step explanation:
1)Non- zeros (1,2,3,....) are always significant.
2)Captive zeros are significant too( zeros between non- zeros ).
3)Trailing zeros (zeros at the end) aren't significant always unless if there is a decimal point.
Such this question we have decimal point so we count them
-- Start with 86.
-- Subtract 9 the first time. You have 77 left.
-- Subtract 9 the 2nd time. You have 68 left.
-- Subtract 9 the 3rd time. You have 59 left.
-- Subtract 9 the 4th time. You have 50 left.
-- Subtract 9 the 5th time. You have 41 left.
-- Subtract 9 the 6th time. You have 32 left.
-- Subtract 9 the 7th time. You have 23 left.
-- Subtract 9 the 8th time. You have 14 left.
-- Subtract 9 the 9th time. You only have 5 left, so you can't subtract 9 again.
You subtracted it 9 times, and you have 5 left.
So 86 divided by 9 is (9 with remainder 5) .
Perimeter=2L+2W
L=W+5, substitute in place of 2L
90=2(W+5)+2W
90=2W+10+2W
90-10=4W
80=4W
80/4=W
W=20, if width is 20 than the length is 20+5=25 cm
You keep the denominator the same so it's D) 7/8
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!
