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3600 divided by 4 =

$25 \times 36 = 5^2 \times 6^2 = (5 \times 6)^2 = 30^2 = \boxed{900}$

$25 \times 36=900$

Simply multiply to obtain $\color{#69047E}{\boxed{900}}$ .

25=5^2. 36=6^2 =(5*6)^2 = 30^2 = 900

Replace $25 = \frac{100}{4}$ , so now we have $100 \times \frac{36}{4}$ , which is equal to $900$

25x30+25x6

=750+150

=900

$25\times36 = 30\times30 = 900$