# Ray

Light ray loses 1/19 of brightness passing through glass plate. What is the brightness of the ray after passing through 7 identical plates?

Correct result:

x =  0.617

#### Solution:

$x=1\cdot \left(1-\frac{1}{15}{\right)}^{7}=0.617=61.7\mathrm{%}$

We would be pleased if you find an error in the word problem, spelling mistakes, or inaccuracies and send it to us. Thank you!

Showing 0 comments:

Tips to related online calculators
Need help calculate sum, simplify or multiply fractions? Try our fraction calculator.

## Next similar math problems:

• Six terms
Find the first six terms of the sequence a1 = -3, an = 2 * an-1
• Tenth member
Calculate the tenth member of geometric sequence when given: a1=1/2 and q=2
• Geometric progression 2
There is geometric sequence with a1=5.7 and quotient q=-2.5. Calculate a17.
• Powers
Express the expression ? as the n-th power of the base 10.
• Classroom 4
In a class of 36 pupils, 2/3 are girls. How much it is in a class girls and boys?
• Five members
Write first 5 members geometric sequence and determine whether it is increasing or decreasing: a1 = 3 q = -2
• Terms of GP
What is the 6th term of the GP 9, 81, 729,. .. ?
• GP - 8 items
Determine the first eight members of a geometric progression if a9=512, q=2
• Geometric sequence 4
It is given geometric sequence a3 = 7 and a12 = 3. Calculate s23 (= sum of the first 23 members of the sequence).
• Find next member
Find x if the numbers from a GP 7, 49, x.
• Missing term 2
What is the missing term for the Geometric Progression (GP) 3, 15, 75,__, 1875?
• Eight palm
There grows 8 palms by the sea. At the first sitting one parrot, on second two, on third sits four parrots on each other twice the previous parrots sitting on a previous palm. How many parrots sitting on eighth palm?
• Mixed with percentages
Calculate 33 1/3% of 570.
• Piano
If Suzan practicing 10 minutes at Monday; every other day she wants to practice 2 times as much as the previous day, how many hours and minutes will have to practice on Friday?
• Quotient
Determine the quotient and the second member of the geometric progression where a3=10, a1+a2=-1,6 a1-a2=2,4.
• Gp - 80
Sum of the first four members of a geometric progression is 80. Determine they if we know that the fourth member is nine times greater than the second.
• Sum of series
Determine the 6-th member and the sum of a geometric series: 5-4/1+16/5-64/25+256/125-1024/625+....