Answer:
18
Step-by-step explanation:
x+x+17+6=49
2x=36
x=18
s1=18
s2=35
s3=6
Answer:
C. 2.0 < t < 2.5
Step-by-step explanation:
time = distance / speed
The circumference of the lake is given by ...
C = πd = 2π miles ≈ 6.28 miles
Then Johanna's time is ...
(6.28 mi)/(3 mi/h) ≈ 2.09 h
This time is in the interval (2, 2.5), so matches choice C.
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<em>Alternate solution</em>
If we take pi to be 3, then this boils down to ...
2×3/3 = 2 . . . hours
Pi is on the order of 5% more than 3, so her time will be on the order of 5% more than 2 hours, or just above 2, but not as great as 2.5 hours. This sort of estimating can get you to the correct answer without a calculator.
Answer:
x = 10
Step-by-step explanation:
Using the rules of logarithms
• log x + log y ⇔ log(xy)
• log
⇔ n log x
• log x = log y ⇒ x = y
Given
ln20 + ln5 = 2 lnx , then
ln(20 × 5) = ln
ln 100 = ln
, hence
x² = 100 ( take the square root of both sides )
x = 10
Answer:
75%
Step-by-step explanation:
we know that 60% of x is 120. we can rewrite this to .6x = 120, to get x we divide both sides by .6, so x = 200. now 120 + 30 = 150. then we divide 150 out of 200 which is .75 it 75%