Indonesian and Tagalog are both classified as members of the Austronesian language family. Nevertheless, they are not considered mutually intelligible. A comparison of the numbers from one to ten reveals that they are related but not so closely.
To compare here are the numbers from one to ten in Indonesian and Tagalog:
Indonesian: satu, dua, tiga, empat, lima, enam, tujuh, delapan, sembilan, sepuluh
Tagalog: isa, dalawa, tatlo, apat, lima, anim, pito, walu, siyam, sampu
The words for the number one bear little similarity to one another. However, they both have the syllable "sa". The number two is different. Here we see that both words start with a "d" and end with an "a" but the Tagalog word is considerably longer. The number three starts with a "t" in both languages, but the words appear to be quite different. In the case of the number four, both words are disyllablic and have the same final syllable. The word five is identical in both languages. The number six is clearly related. In both languages it is disyllabic and shares the nasals "m" and "n". The words for the number seven appear rather different but they are both disyllabic and have a back vowel in the final syllable. The number eight is rather different in both languages but both languages have an "l" as the third segment. With the number nine, the Indonesian word is considerably longer, but in both languages the first segment is an "s" and the final segment is a nasal. In the case of the number ten, the Indonesian word is again longer but both words start with the same segment and share a "p" and a "u". The similarity of the two words is thus evident.
A comparison of the numbers from one to ten in Indonesian and Tagalog reveals that the two languages are related. However, the degree of similarity of the two languages is not as great as it is between other languages such as Czech and Slovak, Spanish and Portuguese and German and Dutch.