Question 7
The two sequences of figures follow the patterns shown. The first four figures in the first sequence contain $1,3,6,10$ circles, and those in the second contain $1,4,9,16$ circles.
An has more than 800 but fewer than 1400 circles. Using every circle, An can make a figure in the first sequence. Using every circle again, An can also make a figure in the second sequence. How many circles does An have?
An has more than 800 but fewer than 1400 circles. Using every circle, An can make a figure in the first sequence. Using every circle again, An can also make a figure in the second sequence. How many circles does An have?