STEP 1: find base area $ B $
To find base area $ B $ use formula:
$$ B = a^2 $$After substituting $ a = 15.2 $ we have:
$$ B = 15.2^2 $$ $$ B = 231.04 $$STEP 2: find lateral surface $ L $
To find lateral surface $ L $ use formula:
$$ L = 2 \cdot a \cdot s $$After substituting $ a = 15.2 $ and $ s = 25.3 $ we have:
$$ L = 30.4 \cdot 25.3 $$$$ L = 769.12 $$STEP 3: find total surface $ A $
To find total surface $ A $ use formula:
$$ A = B + L $$After substituting $ B = 231.04 $ and $ L = 769.12 $ we have:
$$ A = 231.04 + 769.12 $$ $$ A = 231.04 + 769.12 $$ $$ A = 1000.16 $$