Answer:
7:
check if 82°F= 30°C,
we know that 5F =9C+160
F° = (9C+160)/5
we apply the formula to check
(30°C*9 +160)/5 = 86°F
Sahsa is wrong, 30°C=86°F
8 :
BMI =m/h²
Tina : 48,8/1.56²=20.05....
Tina is not underweight
Stephen : 68.5/1.8²=21.1419...=21.14
BMI = 21.14
he wants his BMI =20
we calculate the weight he should weigh
x= weight
20=x/1.8²
x=20*1.8²=64.8
he should weigh 64.8kg for a BMI of 20
he needs to lose 68.5-64.8 =3.7kg