To solve this question, first cross multiply
Let ? = x
4/9 = x/81
4(81) = 9(x)
Simplify.
81 x 4 = 324
324 = 9x
Isolate the x, divide 9 from both sides
324/9 = 9x/9
x = 324/9
x = 36
4/9 = 36/81
36 is your answer
hope this helps!
<span>Chris' average speed is 3.5mph:
Lets take Chris' brother speed = B
then Chris speed = (B+ 1) mph-------given in the question
and:
The average speed for covering 18 miles= chris' average speed + his brother's
average speed = (B+ 1) + B
since Speed = Distance covered / time taken
then average speed for 18 miles can also be found by: 18 miles/3 hours = 6 miles per hour
then we have; (B+ 1) + B = 6mph
(B +1) = (6-B)
B+B = 6-1=5
2B=5
B=5/2=2.5 mph (this is Chris' brother average speed)
Hence Chris' average speed is = B+1= 2.5+1= 3.5mph</span>
There is 20 students. To find the answer you need to use porportionals and cross multiply.
Answer:
im on the same question and i dont know