The answer is b due to pemdas
Answer:
2000 meters
Step-by-step explanation:
When the motorboat is moving downstream, its speed relative to the ground is 18 km/h, so its speed relative to the raft is 15 km/h.
When the motorboat is moving upstream, its speed relative to the ground is 12 km/h, so its speed relative to the raft is again 15 km/h.
Converted to m/min, the relative speed is:
15 km/h × (1000 m/km) × (1 h / 60 min) = 250 m/min
It takes the motorboat 16 minutes to travel to the front of the raft and back. Since the speed is the same in both directions, the motorboat takes 8 minutes to travel the length of the raft.
So the length of the raft is 250×8 = 2000 meters.
Remark
The way you have to set this up is to take the new number for the males and put it over the total for the males and females. The new number for the males / total = 3/5.
Step One
Find the total number of females
100 + 160 = 260 when 100 females have been added to the study.
Step Two
Find the number of males
The total number of males = 240 + x where x is the number of males to be added.
Step Three
Find the total for both
260 + 240 + x = Total
500 + x = Total.
Step Four
Find the ratio of males to total
(240 + x) / (500 + x) = 3/5
Step Five
Cross multiply and solve
(240 + x)*5 = (500+x)*3
1200 + 5x = 1500 + 3x Subtract 1200 from both sides.
5x = 1500 - 1200 + 3x
5x = 300 + 3x Subtract 3x from both sides.
5x - 3x = 300
2x = 300 Divide by 2
x = 300 / 2
x = 150
Check
(240 + 150 ) / (500 + 150) = ? 3/5
390 / 650 = ? 3/5
39/65 = ? 3/5 Divide the top and bottom on the left by 13
3/5 = 3/5 and it checks.
remember that when total value is used a negative number is turned positive so it equals to 282 feet
Answer:
a.....Naeem's work
Step-by-step explanation:
i just took the the test i got it right
