Divide I from both sides then subtract r from both sides, too so in the end:
R= (E-r)/I
Fifthteen(15)xseventy (70)= 1,050
Answer:

Step-by-step explanation:
The result is given by means of some algebraic handling:

- Multiplication of rationals.
- Dividing each term by 2.
- Dividing each term by 2.
- Dividing each term by 3.