Lesson Steps:

Step 1:
Find the Simple Interest for one Year.

Step 2:
Find the Simple Interest for three year.

Step 3:
Subtract the Simple interest for 3years from Amount of 3 years

Answer:

Qn. 2 The Question is based on the Simple Interest For a principal amount.

Initial money ----(after some time)----> Intial money + Interest

Principal --------->Amount

Given:
Principal---- 2years---->6200. i.e Principal + 2year SI=6200
Principal-----3years----->7400.i.e Principal + 3year SI=7400

Subtracting we get One year Simple Interest=7400-6200= 1200$
For 3 years simple interest is 3*1200=3600

Principal + SI(for 3 years)=7400
Principal + 3600 =7400
So Principal = 7400 -3600 =2800.

Answer is 2800$ is the Principal

Grade: 7
Level: Middle school
Subject: Math
Topic: Money