Speed, S = Distance (d) / Time (t) => S= d/t => t= d/S
Let the speed of boat in still water be x mph
Resulting speed upstream = x-4 mph for a distance of 30 miles
Resulting speed downstream = x-4 mph for a distance of 50 miles
Time taken in both distances is equal.
Therefore,
30/(x-4) = 50/(x+4) => 30(x+4) = 50(x-4) => 30x+120 = 50x-200 => 120+200 = (50-30)x => 20x = 320 => x=320/20 = 16 mph
The speed of boat in still water is 16 mph.
Consider the number as 'n' (for now)
3n - 9 = 69
3n = 69 + 9
3n = 78
n = 78/3
n = 26
Therefore, The number is 26
Answer:
Step-by-step explanation:
1)3.8 *10¹⁵
2)4.0*10¹⁴
3)30.4*10⁻²⁰
4)523,000,000,000 atoms
5)0.000 000 000 000 000 000 000 000 00167
16 x 8 = 128 square feet (area of rectangle)
shaded:
8 x 2 = 16
10 x 1 = 10
1/2 (3)(10) = 15
total shaded area: 16+10+15 = 41 square feet
total non-shaded area = 128 - 41 = 87 square feet
answer
area of the shaded region = 41 square feet
area of the non - shaded region = 87 square feet