For a new TV series "Stupidity Factor contestants are dropped into the ocean (p 1030 kg/ms) along with a Styrofoam soo kg/ms block that is mm x 3 mm X 20 cm thick. If too many contestants climb aboard the block and it sinks below the water surface, they are declared "stupid" and abandoned at sea. Find the maximum number of 7o kg contestants that the block can hold. (No fractional contestants, please.

Please Help me very hard need help

1 answer

Your typos make this impossible.
However in general:
Archimedes says:
the force up on the people and block
is equal to the weight , rho *g * volume of water displaced
so
1030 * g * L* w * h = rho of block * g * L * w * h + 70 * g * n
so
n = (1030-rho block)* L * w * H/ (70)