Chapter ISG, Problem 5.1.2.14P

To determine

To define a variable, write and solve an inequality

Answer to Problem 5.1.2.14P

  $x+20\ge 150$

and

  $x\ge 130$ (His balance initially was atleast 130)

Explanation of Solution

Given information:

D deposits $20 in his Saving Account

After depositing $20 his balance is atleast $150

Calculation:

Let balance in D’s account initially be $x$

When $20 is added to initial balance then new balance becomes $x+20$

It is given that After depositing $20 his balance is atleast $150

Therefore the inequality becomes:-

  $x+20\ge 150$

On subtracting 20 from both sides

  $x+20-20\ge 150-20$

  $x\ge 130$

So his initial balance was atleast $130.