A:
Ratio of all students in the class to girls is...
15:8
b:
Ratio of boys to girls....
7:8
Answer:
18c-s
Step-by-step explanation:
Spike. dont. Trust. It
Solution :
Given data :
The mean length of the steel rod = 29 centimeter (cm)
The standard deviation of a normally distributed lengths of rods = 0.07 centimeter (cm)
a). We are required to find the proportion of rod that have a length of less than 28.9 centimeter (cm).
Therefore, P(x < 28.9) = P(z < (28.9-29) / 0.07)
= P(z < -1.42)
= 0.0778
b). Any rods which is shorter than
cm or longer than
cm that re discarded.
Therefore,
P (x < 24.84 or 25.16 < x) = P( -59.42 < z or -54.85)
= 1.052
Answer:
Step-by-step explanation:
27^x = 9÷(3^x)
So (3^3)^x = (3^2)÷(3^x)
So 3^3x = 3^(2-x)
Comparing powers on both sides,
3x = 2 - x
So, 4x = 2
So, x = 1/2
Given ( 27 ) ^ x = 9 / 3 ^x
⇒ ( 3 × 3 × 3 )^x = ( 3 × 3 ) / 3^x
⇒ ( 3 ³ )^x = 3² / 3^x
⇒ 3 ^ 3x × 3^x = 3² [ since ( a ^m)^n = a ^mn ]
⇒ 3^ (3x +x) = 3² [ since a^m × a^n = a ^m+n ]
⇒ 3^4x = 3²
⇒4x = 2 [ since If a ^m = a ^n then m = n ]
⇒ x = 2 / 4
∴ x = 1 / 2
I hope this helps you.