Amount of Social security received by Fred = $900
Martha receives 60% of the amount of social security received by Fred.
Amount of social security received by Martha = $900 x 60%
= $540
Total amount received by both Martha and Fred = $1800
Social security (Fred) + Social Security (Martha) + Pension amount (Fred) = $1800
$900 + $540 + pension amount (Fred) = $1800
Pension amount (Fred) = $1800 - $900- $540
= $360
Therefore, Fred must receive $360 from his pension.