Hi people, please if someone can give me a hint with this, l got it but Maths watch doesnt recognise it as 100% right so what is wrong here? thanks in advance, have a good day

 lower bound = 3.107

                upper bound = 3.161

Step-by-step explanation:

Circumference = 213

lower bound is 212.5 (because it rounds up to 213)

upper bound is 213.4 (because it rounds down to 213)

Note: 213.5 rounds up to 214

Diameter = 68

lower bound is 67.5 (because it rounds up to 68)

upper bound is 68.4 (because it rounds down to 68)

Note: 68.5 rounds up to 69

Circumference ÷ Diameter

Lower ÷ Lower: 212.5 ÷ 67.5 = 3.148

Lower ÷ Upper: 212.5 ÷ 68.4 = 3.107       LOWER bound (smallest value)

Upper ÷ Lower: 213.4 ÷ 67.5 = 3.161        UPPER bound (largest number)

Upper ÷ Upper: 213.4 ÷ 68.4 = 3.120

Lalo can talk for 715 minutes more in that month if he has already talked for 785 minutes.

Step-by-step explanation:

Total number of minutes per month lalo has on his cell phone plan = 1500

Number of minutes he has already talked in that month = 785

Number of minutes available to talk = total number of minutes he has - total number of minutes he has already used.

                                                           = 1500 - 785

                                                            = 715 minutes.

Thus, Lalo can talk for 715 minutes more in that month if he has already talked for 785 minutes.