NOTE THIS IS AN EXAMPLE:
Let t = time, s = ostrich, and g = giraffe.
Here's what we know:
s = g + 5 (an ostrich is 5 mph faster than a giraffe)
st = 7 (in a certain amount of time, an ostrich runs 7 miles)
gt = 6 (in the same time, a giraffe runs 6 miles)
We have a value for s, so plug it into the first equation:
(g + 5)t = 7
gt = 6
Isolate g so that we can plug that variable value into the equation:
g = 6/t
so that gives us:
(6/t + 5)t = 7
Distribute:
6 + 5t = 7
Subtract 6:
5t = 1
Divide by 5:
t = 1/5 of an hour (or 12 minutes)
Now that we have a value for time, we can plug them into our equations:
1/5 g = 6
multiply by 5:
g = 30 mph
s = 30 + 5
s = 35 mph
Check by imputing into the second equation:
st = 7
35 * 1/5 = 7
7 = 7
Answer: 2/3
Step-by-step explanation: In this problem, we have 8/15 ÷ 4/5. Dividing by a fraction is the same as multiplying by its reciprocal. In other words, we can change the division sign to multiplication and flip the second fraction.
8/15 ÷ 4/5 can be rewritten as 8/15 × 5/4
Now, we are simply multiplying fractions so we multiply across the numerators and multiply across the denominators.
8/15 × 5/4 = 40/60 = 2/3
Answer:
1 mile = 15 seconds
Step-by-step explanation:
3 minutes and 15 seconds = 3 min + 15 sec
1 minute = 60 seconds
15 seconds =15/60 = 0,25 min
then
3minutes and 15 seconds = 3.25 minutes
13miles in 3 minutes and 15 seconds
= 13 miles / 3.25 minutes
= 4 miles / 1 minute
every minute Jose ran 4 miles
then:
4 miles is a 1 minute
1 mile is a T minutes
T = 1*1/4
T = 1/4 minute
1 minute = 60 secomds
1/4 minute = 60*1/4 = 60/4 = 15 seconds
