You will be given a definition of a task first, then some input of the task.
This task involves creating questions from a given passage that involve some kind of complex reasoning (including numerical reasoning).
The generated questions must require looking at more than one part of the passage to answer. Try to use a variety of reasoning types in your questions (some of the sample reasoning types are illustrated in the 'positive examples' field) and also have a variety of answer types (spans, numbers, dates). A span is a continuous phrase taken directly from the passage or question. In such questions, the answer spans are recommended to be five words. Questions with answer type "number", are expected to start with "How many". For instance, "How long did an event last?" can be phrased as "How many years did an event last?". To increase diversity, try to create more questions for which the answer will be multiple spans. Please create questions that require AT LEAST 2 arithmetic operations as illustrated in the 'positive examples' field. You are encouraged to try DIFFERENT COMBINATIONS of operations and not just limit to the combinations shown in those examples. The more challenging questions you create, the better it is.

Passage: In December 1774, a Siamese supported rebellion broke out at Lampang in Lan Na, and soon spread. On 15 January 1775, the rebels took Chiang Mai, and overthrew the Burmese installed government. In November 1775, two Burmese armies of 35,000 were to invade Lan Na and Siam. But because of a mutiny by a senior commander, the southern army lost a significant portion of the troops. The remaining Burmese armies fought their way in. The northern army managed to capture Chiang Mai, albeit at a great cost, and the southern army took Sukhothai and Phitsanulok in central Siam. However, the invasion forces were too small to overcome the Siamese defences, and were bogged down. The armies withdrew in June 1776 after Hsinbyushin died. Hsinbyushin's successor Singu stopped the war with Siam, and demobilised much of the army. The decision was well received by the war-torn country. The people had grown tired of constant conscriptions to fight in "ever-lasting wars" in remote regions they had never heard of. But the king had unwittingly given up Chiang Mai, which proved to be the end of two centuries of Burmese rule there. Likewise, Singu took no action in 1778 when Vientiane and Luang Prabang stopped paying tribute, and came under Siam's sphere of influence.
Output:
How many armies were there?