Write the hours as ratio
Carrie : Jerry
2 : 5
Put this ratio in words, we say 'for every two hours Carrie takes to inspect a case, Jerry would need 5 hours'
Carrie has done 30 minutes on a case before taking a break. It means Carrie has 1.5 hours left on the case if she was to continue it.
We need to work out the proportion of the time Jerry would take in comparison to 1.5 hours that Carrie would have taken.
First, we divide 2 by 1.5 ⇒
Then we divide 5 by 4/3 ⇒
hours
Jerry would have taken 3.75 hours to finish the rest of the case
<span>The median of a set of three numbers is x. there at least three numbers in the set. Write an algebraic expression, in terms of x, to represent the median of the new set of numbers obtained by
a] </span><span>adding 1/8 to every number in the set
Let the numbers be w,x,y
adding 1/8 to the number we get:
(w+1/8),(x+1/8),(y+1/8)
the new median will be:
(x+1/8)
</span><span>b. subtracting 9 1/4 from every number in the set
Given our data set is w,x,y
adding 9 1/4 to each number we get:
(w+9 1/4),(x+9 1/4), (y+9 1/4)
thus the new median is:
(x+9 1/4)
c]</span><span>multiplying -5.8 to every number in the set and then adding 3 to the resulting numbers
Multiplying each number by -5.8 we get:
(-5.8w),(-5.8x),(-5.8y)
adding 3 to these numbers we get:
(-5.8w+3),(-5.8x+3),(-5.8y+3)
thus the new median is:
(-5.8x+3)
d]</span><span>dividing every number in the set by 0.5 and then subtracting 1 from the resulting numbers
dividing each number in our set by 0.5 we get:
(w/0.5),(x/0.5),(y/0.5)
this will give us:
(2w),(2x),(2y)
then subtracting 1 from the above we get:
(2w-1),(2x-1),(2y-1)
thus the median will be:
(2x-1)
</span><span>e. adding 7.2 to the greatest number in the set
from our set:
w.x.y
the greatest number is y, then adding 7.2 to the greatest numbers gives us:
y+7.2
thus new series is:
w,x,y+7.2
thus the median is:
x
</span>Conclusion
The median doesn't change<span>
</span><span>f. subtracting 4.2 from the least number in the set
</span>from our set w,x,y; subtracting 4.2 from the least number gives us:
w-4.2
the new set is:
w-4.2, x, y
thus the new median is x
Conclusion
The median doesn't change
Scale factors are multipiled
a times scale factor turns into b
so
0.5 times scale factor=0.8
divide both sides by 0.5
scale factor=1.6
the scale factor is 1.6
