Question

Approximate ratio of the strength of the cement concrete in 7 days to that of 28 day

Answer 1

one isto four ok understand

Answer 2

The ratio of the strength of the cement concrete in 7 days to that of 28 day is 0.6.

You must use limited water to make the concrete base with cement because much water can segregate the cement and remove the sand from the concrete solution.

The lower ratio of water can make the cement harder and the lower ratio of water can make the concrete durable.