Molecular weight of NaBr=23+80=103 approx.
1000ml of NaBr solution contains 103g of the solute (1 mole).
But the higher concentration means that 1000ml contains 3.60×103=370.8g of solute (3.60M).
62.9g therefore requires 62.9/370.8×1000=169.63ml, about 170ml of 3.60M molar solution.