Question 1
Positive numbers are written in order beginning with 1 in the pattern shown. A cross encloses five numbers; the example has centre 25.
(a) The sum of the numbers enclosed by a cross with centre 72 is 361. What is the sum for centre 75?
(b) What is the largest number enclosed by the cross with centre 103?
(c) A cross encloses numbers with sum 1151. What is its centre number?
(a) The sum of the numbers enclosed by a cross with centre 72 is 361. What is the sum for centre 75?
(b) What is the largest number enclosed by the cross with centre 103?
(c) A cross encloses numbers with sum 1151. What is its centre number?