Answer:
is the expression which is equivalent to
.
In other words:

Step-by-step explanation:
Given the expression

solving





∴ 
Thus,

Therefore,
is the expression which is equivalent to
.
The rule of exponential multiplication is (a^x)*(a^y)=a^(x+y)
using this with your expression, we can do
(10^1)*(10^3)*(10^2)=10^(1+3+2)=10^6
Final answer:
10^6 or 1 million
Hope I helped :)
I'm assuming it's 57. Because 1/2 can equal .5 and 56.5+.5=57
Number of students = 26
Number of students without siblings = 4
⇒ Number of students with at least one siblings = 26 - 4 = 22
Number of students with brothers = 17
Number of students with sisters = 7
⇒ Number of students with both a brother and a sister = 17 + 7 - 22 = 2
P(student has a brother, given that they have a sister) = 2/7
Answer: 2/7