Answer: 1/7
Step-by-step explanation:
7x=1
x=1/7
The <em><u>correct answer</u></em> is:
7.8 × 10⁷
Explanation:
To write a number in scientific notation, we want the decimal behind the first non-zero digit in the number. The first non-zero digit in 78 is 7; this means we want 7.8. In order to have the decimal point behind the 7, we need to move the decimal 7 places. This is the exponent of 10 in our scientific notation, which gives us
7.8 × 10⁷
You can build a cylinder in two ways: either you draw a circle on a plane, and "raise" it perpendicularly to the plane itself, or you start with a rectangle, and rotate it around one of its sides.
For these reasons, if you cut the cylinder with a plane parallel to the base you have a circular cross section, while if you cut the cylinder with a plane perpendicular to the base you have a rectangular cross section.
-- The whole discussion involves 4 rooms, never more and never less,
so we can call the 4 rooms "1 job" for simplicity.
-- Patrice, by himself, does the job in 10 hours. So he does 1/10 of
the job each hour.
-- Working together, Patrice and April do the job in 6 hours. So when
they work together, they do 1/6 of the job each hour.
-- April's part of the job is (1/6 - 1/10) = (5/30 - 3/30) = 2/30 = 1/15 job per hour.
-- Her unit rate alone is 1/15 job per hour, or <em>15 hours</em> per job.
