Your figures are the stuff of BNP posters. The 2.75 million figure is higher than any authoritative figure that I have seen. The 6.5% growth rate if based on such a 'high' figure and projected back to a lower than correct figure from some base period would also then be incorrect by a significant margin. Even from your own figures your calculations are wrong.The 7% figure would only affect the ration of the two populations. A 6.5% increase doubles in 11 years not 10. the difference in growth rates between Muslim and non Muslim makes no difference to the absolute number of Muslims. Even accepting your incorrect data, a projection from a figure of 2.75M to 88M takes 55 years not 50. However your figures also do not allow for falls in birth rate which normally occur in immigrant populations as they adapt culturally and economically to some extent at least, in later generations.
NATO backs Turkey's fight against ISIS (Reuters)
from the article: Iranian threat to destroy Israel doesn't hold up