Answer:
21 N
Step-by-step explanation:
let mass be m and weight be w
Given w varies directly with m then the equation relating them is
w = km ← k is the constant of variation
To find k use the condition m = 7 , w = 49 , then
49 = 7k ( divide both sides by 7 )
7 = k
w = 7m ← equation of variation
When m = 3 , then
w = 7 × 3 = 21 N
These numbers are not irrational .
They are all whole numbers with no decimal points and ongoing numbers.