Question
In a school there are 20 girls. The average age of the
girls is decreased by 2 months when one girl aged 18 years is 8 replaced by a new girl. What is the age of the new girl?Solution
Let the sum of age of 19 girls be x years and the Age of the new girls be y years. Old Average = (Sum of the age of 19 girls + Age of the girl to be replaced)/Total number of girls => (x + 18) / 20 New Average = (Sum of the age of 19 girls + Age of the new girl) / 20 According to the question, As we know The average age of the girls is decreased by 2 months when one girl aged 18 years is replaced i.e. Old Averag - New Average = 2 month ⇒ {(x + 18)/20} – {(x + y)/20} = (2/12) ⇒ 18 – y = 10/3 ⇒ y = 44/3 years ⇒ y = 14 years 8 months ∴ The age of new girl is 14 years 8 months.
Which cells are responsible for producing the myelin sheath in the nervous system?
Which type of drainage pattern is characterized by streams that resemble branches of a tree?
Which gland functions as the body's thermostat?
Which of the following represents the pair of sex chromosomes in men?
What is the powerhouse of the cell.
Which of these statements are accurate regarding the molecular structures of DNA and RNA?
Statements:Â
1. DNA is a doublestranded molecul...
Which is the smallest bone in the human body?
Which phylum does the genus 'Fasciola', known as liver flukes, belong to?
An organism feeding on multiple hosts in its lifetime is called-
What is the smallest unit of life.