Question

A mobile phone and its case cost ₹ 1100 in total. The price of the mobile"
"phone is ₹ 1000 more than its case. What is the price of the mobile phone?"

Answer 1

Answer:

cp={$105}

PREMISES

ASSUMPTIONS

Let pc=phone case

Let cp=cell phone

Let the cost of the phone case=pc

Let the cost of the cell phone=pc+$100

CALCULATIONS

cp+pc=$110

(pc+$100)+pc=$110

2pc+$100=$110 (Addition is commutative)

2pc+($100-$100)=$110-$100

2pc+0=$10

2pc=$10

2pc/2=$10/2

pc=$10/2

pc=

$5

and,

if cp=pc+$100, then

cp=$5+$100

cp=

$105

PROOF

If cp=$105, then the equations

cp+pc=$110

$105+$5=$110 and

$110=$110 establish the root (zero) cp=$105 of the sum of cp+pc

Step-by-step explanation: