3. The weights to be shown on the plate in respect of—
(a)item 9 in Part I shall be the weights shown at item 6 in that Part and in respect of item 7 in Part II shall be the weights shown at item 4 in that Part, in each case reduced so far as necessary to indicate the maximum weight applicable to each axle of the vehicle, if the vehicle is not to be used in contravention of regulations 28, 87, 90 or 91, and if the tyres with which the vehicle is equipped are not, as respects strength, to be inadequate to support the weights to be so shown at item 9 and item 7;
(b)item 10 in Part I shall be the weight shown at item 7 in that Part and in respect of item 8 in Part II shall be the weight shown at item 6 in that Part, in each case reduced so far as necessary to indicate the maximum permissible weight applicable if the vehicle is not to be used in contravention of regulation 86 if the tyres with which the vehicle is equipped are not, as respects strength, to be inadequate to support the weights to be so shown at item 10 and item 8.