740-707.60=32.40
707.60-675.20=32.40
675.20-642.80=32.40
so that means every month you are paying 32.40$ bill. to get how many months you can pay phonebills without depositing any more money devide the 740/32.40=22.83 but you can not pay bill for the 0.83 month so answer will be 22 months
The formula for the circumference is 2πr.
The diameter d is given, which is 2 times the radius r (d = 2r)
So you have to calculate π d = 3.142×1.8 ≈ 5.7
The answer would be -4 because you are dividing by -5