Answer:
15 minutes
Step-by-step explanation:
Their rate together is 1/6 floor per minute.
Her rate alone is 1/10 floor per minute.
His rate is the difference of these:
1/6 - 1/10 = 5/30 -3/30 = 2/30 = 1/15 . . . . floor per minute
It would take Jacob 15 minutes to do it alone.
6x - 10 = 8
6x = 18
x = 3
the answer is b
Answer: 1080 km.
Explanation: Since she bikes 30 weekends per year, and for each of those 30 weekends she rides 9km, we can simply multiply 30*9 and find that she bikes 270km a year. However, the question asks how much she bikes in four years. To solve for this we can multiply our yearly distance by four, resulting in 1080 km.
Answer:
(20+2)(20-2) = 20^2 - 2^ = 396
Step-by-step explanation:
Difference of two squares is breaking down numbers into pieces and using the distributive property to solve. The pieces should be in the form (a-b)(c+d).
Write 22 as (20 + 2) and 18 as (20-2).
(20+2)(20-2) = 400 + 40 - 40 - 4 = 400 - 4 = 20^2 - 2^ = 396